The next milestone should add something you actually want to your ordinary life.

Goals get chosen for how they sound rather than for what they change on a Wednesday. A title, a number, or a finish line can be genuinely worth having, or it can leave your actual days identical while costing a year. The useful test is not whether the milestone is impressive but whether the life on the other side of it holds more of what you like.

Describe an ordinary day after the goal is reached, hour by hour. If it looks the same as now, ask what you were really after and adjust the target.