mistime
To do something at the wrong time so it fails.
To mistime something means to do it at the wrong moment, when the timing doesn't work out the way you planned. A basketball player mistimes a jump and misses the rebound. A comedian mistimes a joke and delivers the punchline before the audience is ready to laugh. You might mistime a jump rope entrance and trip over the rope, or mistime asking your parents for a favor right when they're stressed about something else.
Timing matters enormously in many activities. In baseball, batters try to time their swing perfectly to meet the ball, but if they swing too early or too late, they've mistimed it. Musicians playing together must match their timing precisely, and a single mistimed note can throw off an entire performance.
The word can also apply to larger decisions. Someone might mistime a joke during a serious conversation, or mistime a request for help when everyone's already overwhelmed. A mistimed remark can hurt someone's feelings not because of what was said, but because of when it was said. Getting the timing right often requires paying attention to what's happening around you and thinking ahead about when your action will have the best effect.