The promotion that lost you the IC
He was the best engineer on the team. You promoted him to manager. Six months later he was unhappy, the team was slower, and you'd traded a tier-one IC for a tier-three manager.
A founder I worked with promoted his strongest engineer to engineering manager last spring. The engineer had asked for it. The founder agreed because the engineer was, by every visible measure, the most senior person on the team. Six months later the team was slower, the new manager was unhappy, and the founder confessed to me that he had probably traded a tier-one IC for a tier-three manager.
The trade is so common it should have a name. The skills do not transfer. The best IC is the person who can solve hard problems alone in a four-hour stretch. The best manager is the person who can resist the urge to solve hard problems alone in a four-hour stretch. These are not the same person. They are usually opposite people. The promotion ceremony does not change which one you are.
The cost is paid in two places at once. The first is the team's velocity, because the new manager is now spending time in one-on-ones and Slack threads instead of in the code that used to move twice as fast as anyone else's. The second is the new manager's own happiness, because the work that made them senior — the deep individual problem-solving — is now structurally inaccessible. They are doing different work for the same hours, and the new work is worse for their brain.
The structural cause is almost always the same. The company has one ladder. The ladder is management. There is no way to pay a senior engineer more, give them more visibility, or grow their title without converting them into a manager. The promotion is not a promotion. It is a compensation hack with an org-chart side effect. The hack works for the company on the books and breaks the team on the floor.
The fix is a senior IC track with real money and real status. A staff engineer who out-earns the engineering manager. A principal who reports to the CTO and shows up in the same all-hands slot. The org has to demonstrate, in compensation and visibility, that the IC track is a real path, not a consolation prize. Most companies under three hundred people do not have this. The ones that do retain their best technical people much longer.
The other half of the fix is to make the manager promotion deliberate, not default. The engineer must have asked for it, demonstrated coaching behavior unprompted, and have access to a real alternative. If the alternative does not exist, the choice is not a choice. The promotion is structural.
The next time you are about to promote your strongest IC to manager, ask whether you are giving them a career path or a pay raise. If it is the second, fix the comp structure. The team will thank you. The IC will stay being the IC. The manager you hire externally will be a manager because they wanted to be one, which is the only kind of manager worth having.