A better conversation would be: "In order to get raise X% you need to do A, B, and C. In order to get raise Y% you also need to do D and E. We will checkpoint 4 times per year on progress, and you'll know well in advance if you've made it." Where A-E are things the employee has direct control over, i.e. not dependent on things like overall team success or company stock price.
The fiction must be maintained at all costs that the employee was the perfect fit at hiring time; neither overqualified aka too expensive or underqualified aka the manager screwed up.
People change, companies change, the business changes. The person you needed when you hired him might not be the exact person you'll need in a year, but a good manager will first see if that person can grow into a new role instead of firing him and hiring someone else.