Well, traditionally, going right takes you through all the monsters and traps to the final treasure chamber, then after the boss battle there's a quick exit that takes you straight back to the entrance down a disused passage. That's the one on the left ...![]()
This actually happened to us once. We have one player who always turns left, so my friend who was guest-DMing for the session, designed an adventure where all the foes were on the left, and the end treasure was on the right.
When the actual session got underway, the "turn left" player couldn't make it, and I assumed the role of party leader... and turned right. One encounter and the adventure was over!
Wow... that was 10 years ago, and I still play with both of them!

Cheers!