Late again? Notice it’s always by the same ten minutes. That’s not traffic. That’s your plan.

Random causes produce random amounts of lateness. When you are consistently off by the same margin, the cause is not the road or the bus, it is the arithmetic you did before leaving. You built the plan around the best possible version of every step, and the missing ten minutes is the gap between that and real life.

Add the usual margin into the plan instead of promising to hurry. Set the leaving time rather than the arrival time, and set it ten minutes earlier than feels necessary. Try that for a week.