It's a trap!
A lot of people say 2-3-15 minutes. I was doing 30 second-1 minute sprayings, several times a day for my babies and juvies.
Then I took the advice of the forum and was doing 2-3 minute mistings.
I lost a juvie female to a respiratory infection. This is in a screen, drained enclosure, it was just too much moisture for her and I lost her within 3 days of doing the 2 & 3 minute mistings.
The adults, YES absolutely do 2-3-15 minutes. Any chameleon under 7 months, IMO and experience, should be no more than 1 minute mistings.
From 1-3 months I hand spray, or misting is set up for only twice a day, 30 seconds.
From 3-5 months it's 5 times a day, 30 seconds to 45 seconds. For 5-7 months old it's 1 minute or so, 3-4 times a day, and for adults it can be whatever you want.