The bath or shower wheel handles a small end-of-day negotiation that is rarely about hygiene. You know how to get clean. What you are really weighing is whether tonight has room in it for twenty-five slow minutes, or whether you should be efficient again and be out in six. That question can hold you in a doorway for longer than the bath would have taken to run.
A bath is a decision to stop. It costs hot water, time, and a little nerve about the evening you are spending, and it pays you back with legs that stop aching and a chapter of something read in peace. A shower is the sensible one: quick, hair washed, no waiting, back to the rest of the night. Neither is the indulgent choice and neither is the virtuous one.
Spinning takes the negotiation out of your head and puts it on a dial with an even chance each side, drawn from your browser's cryptographically secure random generator. The interesting part is your reaction. If Shower lands and you feel genuinely let down, you have just learned you needed the twenty minutes, and you are allowed to overrule a wheel whose only job was to tell you that.