Slowing down can reveal mistakes speed was helping you outrun.

Constant speed can keep you ahead of the consequences of your own mistakes. The unfinished conversation, the sloppy decision, the thing you have not wanted to look at, all stay behind you as long as you keep moving. When you slow down they catch up, which is uncomfortable and also the only way they get addressed.

If slowing down brings a wave of things you would rather not think about, take that as the reason to stay slow a little longer. Handle one of them. Speed was managing them, not solving them.