Couldn't agree more. My PIN is triggered several times a day if I'm active. I have to wear it super tight for it not to trigger the locking pin. Ugh. Wish it was just for the Samsung Pay app, not the whole watch. Or that it didn't lock when a watch comes loose for 1/2 second on your wrist. So annoying.
If you want to you can turn on the heart rate monitor to continous and then it won't do this until you physically take the watch off. That way you don't have to wear it super tight and it estimates calories burned much more effectively.