The radiator caps in all cars seem to be very tightly installed. In some cars (at least in my 2011 Toyota Yaris), the radiator cap is not round so you can remember the position it was at, but in other cars the radiator cap is round and there is thus room for mistightening it. Now suppose I remove and reinstall the radiator cap but forget to tighten it as well as it was tightened previously.
What problems could such loose radiator cap cause?
Can the coolant evaporate through the loose cap, requiring filling up the coolant?
Is it possible that the engine overheats if the radiator cap is slightly loose?
I found a related question, Can a loose radiator cap cause P0420? where it was asked whether a loose radiator cap could cause an error code. However, there was no question about other problems that a loose radiator cap could cause.