For the sake of discussion and be cause i didn't see the original post...
Chameleons are solitary creatures and ambush predators. they feel best when they think no one knows they are there. Handling them destroys this feeling for them.
sometimes it is necessary to handle them, to move between cages, medicate etc.
Here are some good references. https://www.chameleonbreeder.com/podcast/ep-80-handling-your-chameleon/