Showering with a Series 5 Watch

Soap is a Surfactant which allows water to break surface tension and penetrate into tighter spaces. Soap can also dissolve or other wise damage seals.

https://support.apple.com/en-us/HT205000

If I were you I would NOT wear the watch in the shower. It is water RESISTANT but in the shower you might get soap in or around the crown and the water might be too hot. Play it safe and keep your watch out of the shower.

Water resistant means that it will resist any water trying to get into the watch up to a depth of 50m,any deeper than that that and it's goodnight eileen for the watch.

2nd this is the water lock button and it comes into play when you go swimming,when the lock is on it prevents any accidental screen touches that may mess up your swim workout.And when you finish swimming turning it off makes the watch vibrate and eject any water that MAY have entered the watch.

3rd While you can shower with an apple watch on in theory, it's not recommended. Your apple watch is water-resistant – not waterproof – and the full act of showering (specifically applying soaps, soapy water, and shampoo) can damage the device and negatively impact an apple watch's water resistance.If you do wear it in the shower then at least put the water lock on