Maze duration vs happiness

[Woodpecker]

When it comes to mazes, how does RCT calculate the amount of time a guest is happy to be in a maze before thinking "I want to get out"?  

After experimenting it seems duration is more important than difficulty per se.  Most of my puzzle mazes get everyone out in about two to three minutes of real time but I'm wondering how far I can push the envelope.

[DUBBO16]

Max for me is around 4-5 minutes but im not a expert.  You can maybe push it further