The Succession Readiness Gap: Why Talent Management and Leadership Development Keep Failing Each Other
Key Takeaways
Succession plans rarely fail because of one missing piece. Usually, a talent management gap and a leadership development gap open up at the same time.
Two structural problems sit on the talent management side: frameworks too complex to act on, and processes done to employees rather than with them.
Three sit on the development side: thin diagnosis, learning that never leaves the classroom, and programmes that run in isolation from one another.
Structured leadership development delivers a 32% lift in people performance and a 23% lift in organisational performance, according to the Chartered Management Institute.
Succession planning is already broadening past the top team: Korn Ferry finds roughly half of organisations now include mid-level managers in succession efforts.
Nearly one in three CEOs exit with little notice, according to Egon Zehnder's analysis of major global companies.
The fix is a single connected system that tracks who is being developed, why, and whether it's actually working.
Somewhere in a mid-sized organisation right now, a named successor is doing everything right: a development plan, time in the coaching programme, two years of strong potential ratings from her manager. On paper, when the role opens up, she is ready.
Then the role opens up, and she isn't.
It's a familiar story: most succession plans look credible in the boardroom and collapse under real conditions. Structured leadership development works: organisations that invest in it see, on average, a 32% increase in people performance and a 23% increase in organisational performance [1]. Development itself isn't the weak link. Closing the succession readiness gap depends on two systems working together, and in most organisations, only one of them gets fixed at a time.
The Successor Who Was Never the Problem
When a ‘ready now’ successor turns out not to be, the instinct is to look at the person: did she get enough coaching, did she want it enough, was the potential rating wrong?
Nearly always, the answer sits somewhere else entirely. Readiness comes from two separate systems working, or failing to work, together: how the organisation manages and tracks its talent, and how it develops people once they've been identified. When either system breaks down, the successor absorbs the blame for a failure that was designed in long before she ever sat the coaching programme.
Two Different Kinds of Broken, on the Talent Management Side
Talent management breaks down in two specific ways. Complexity is the more visible one. Most talent frameworks were built for a different era, categorising people into boxes and running calibration meetings that consume hours before the ratings ever get filed away and forgotten. The output looks rigorous. In practice, it consumes the time that should have gone into an actual, simpler development conversation, and by the time it's finalised, the data has often gone stale.
The other is that talent decisions are still made to people rather than with them. Career conversations, where they happen at all, tend to run one way: a manager assessing, an employee listening. Many employees never learn their own succession status, sometimes because the organisation worries about raising expectations, sometimes because it worries about the opposite, that naming someone as a successor makes them easier for a competitor to poach. Either way, aspiration and plan drift apart, unrecorded and unrevisited.
Both problems cost the same thing in the end: a talent process nobody quite believes in, producing successors nobody is confident about, whatever the org chart says.
Where Development Quietly Fails to Produce Readiness
Development fails for three further reasons, each just as structural. Weak diagnosis is the most basic of them. A high-potential rating and a solid performance review tell you very little about what specifically stands between someone and their next role.
Development built on incomplete information produces generic results: the same leadership programme for everyone, regardless of what each person is actually missing.
A second reason is that development too often stays where it's easy to deliver, rather than where it transfers. Up to 75% of what's learned in a classroom is forgotten within a week without real application [2]. Real capability is built through the decisions people make under pressure, rather than the frameworks people hear about in a workshop. Development that never leaves the training room rarely shows up when it matters, and development that happens invisibly never builds the one thing senior transitions actually depend on: the trust of the people who will be signing off on the promotion.
Fragmentation is the third failure: a coaching engagement running here, a 360 review running there, a stretch assignment handed out with no structure around it. Each has value on its own. None of it compounds, because nothing ties the pieces together, and leaders end up technically ‘in development’ and practically no further along than when they started.
The Succession Readiness Gap Nobody's Watching
What makes this hard to fix is structural, not managerial. These five problems rarely get diagnosed together, because in most organisations they don't report to the same person or sit on the same calendar. Talent management runs on an annual review cycle, owned by HR. Leadership development runs on whatever the training budget allows, owned by L&D. The two teams may barely compare notes, and the data that would connect them, who is coming up for succession and what specifically they need to be ready, rarely moves between the two.
This is the gap that swallows the other five. An organisation can fix its talent framework and still fail its successors, because the development that follows is undiagnosed and disconnected. It can run beautifully designed leadership programmes and still get blindsided, because nobody connected the output to an actual succession decision. Readiness fails when the two sides are never knitted together into a single, continuously updated picture of who is ready, for what, and why; neither side has to be broken on its own for that to happen.
Closing that gap means treating talent management and leadership development as one connected system rather than two adjacent initiatives: a shared, ongoing view of where people sit, considerably simpler than a 9-Box Grid can offer, paired with development that starts from a real diagnosis of what each person specifically needs rather than a generic programme applied uniformly. Each half depends on the other to actually work.
“We were losing people we didn't want to lose.” Sam Turner, Senior HR Business Partner, Chugai Pharma Europe, whose team's talent management rollout achieved 98% completion of career conversations within three months of launch.
Why This Gets More Urgent, Not Less
The stakes for closing this gap keep climbing. Succession planning is already reaching further down the organisation. Korn Ferry's research finds that roughly half of organisations now include mid-level managers in succession efforts, up from a focus reserved almost entirely for the top team [3]. That's a considerably wider group whose readiness now needs to be tracked accurately.
At the same time, the cost of getting it wrong hasn't gone away. Egon Zehnder's analysis of major global companies found that nearly one in three CEOs exit with little notice, leaving boards without a contingency plan [4]. Most organisations will never see a leadership exit that dramatic, but every organisation has its own version of it: a resignation that lands without warning on a Friday, or a retirement announced with far less runway than anyone expected. An unready bench doesn't announce itself until the moment it's tested.
Where readiness sits | Run separately | Knitted together |
Who owns the picture of readiness | HR holds succession data, L&D holds development data, the two rarely meet | One shared, continuously updated view spanning both |
What triggers development | Whatever the training calendar allows this quarter | A specific diagnosed gap tied to a specific succession decision |
What happens when a role opens | HR checks who was rated ready, and finds out how ready in reality once it's too late to fix | The gap between rated and actual readiness is already visible and already being closed |
What a successor experiences | A generic programme, applied to everyone regardless of their real gap | Development built around what they are specifically missing |
Two Questions, Not One
The organisations that get succession right stopped treating ‘who's ready’ and ‘how do we get them ready’ as two separate questions with two separate owners, rather than simply out-investing everyone else in framework sophistication or development budget. Our new handbook, Developing Leaders, Securing Succession, sets out what it actually takes to close that gap and keep it closed.
Frequently Asked Questions
Why does succession planning fail even when a named successor has been given real development?
Because readiness depends on two systems working together. A strong development programme still won't produce a ready successor if the underlying talent process never diagnosed what that person specifically needed, or if the two processes were never connected in the first place.
Is this the same problem as the 9-Box Grid being too complex?
It's part of the same problem, but broader. An over-complex talent framework is one of the structural issues that undermines readiness. Even organisations that simplify their framework can still fail if the leadership development that follows isn't diagnosed, connected to real work, or joined up across programmes.
How can HR and L&D teams start connecting talent management and leadership development without adding a new layer of process?
The starting point is data: a shared, regularly updated view of who is coming up for succession and what specific development gap each person has, rather than two separate systems that happen to discuss the same people once a year.
What does readiness actually mean, if not a high-potential rating?
Readiness is current capability under real conditions. Potential that might develop given more time is a different thing entirely, and it's a poor basis for a promotion decision. Someone can be technically strong and perform well in development settings and still fall short when the pressure is genuine and the stakes are real.
References
[1] Chartered Management Institute / SHRM. Research on the impact of structured leadership development. Available at: https://www.shrm.org/hr-today/news/all-things-work/pages/how-learning-and-development-can-attract-and-retain-talent.aspx
[2] Murre, J.M.J. and Dros, J. (2015) Replication and Analysis of Ebbinghaus' Forgetting Curve. PLoS ONE, 10(7): e0120644. Available at: https://doi.org/10.1371/journal.pone.0120644
[3] Korn Ferry (2026) Revamping Succession. Korn Ferry Institute. Available at: https://www.kornferry.com/institute/revamping-succession-planning
[4] Egon Zehnder. When to Trigger a CEO Succession. Available at: https://www.egonzehnder.com/what-we-do/ceo-successions/insights/when-to-trigger-a-ceo-succession
