Unless you're carrying a pager, as an engineer you don't really need to think about work when you're off the clock. Culturally this tends to happen a lot, but it's not mandatory.
I don't mean that I _have_ to think about it, it's more that any problems that existed at the end of the day will exist the next day. There's no reset because there's no second shift coming in after me. That causes me to think about the problem, at least subconsciously, until I can fix it.
When I worked in food service, any problem that came up that wasn't solved when my shift ended, would likely still be fixed by the time I worked next.