Gloves give you a wrong feeling of beeing 'clean'. You are'nt clean when you first put them on, and as soon as you touch anthing on the outside, your gloves are contaminated and if you work in analysis that sucks (there obviously are situations where you should wear gloves - sometimes even to the elbow). However, if you wear gloves, you will be tempted to think "ah what the hell, I am wearing gloves!" and ruin all the work you did that day. You immediately notice when something touches your hands and wash them, you just dont care when it touches your gloves and dont swap them for a new pair.

Gloves give you a wrong feeling of safety. If you wear gloves the whole day, you tend to feel safer, but you arent neccessarily. Compared to people who only put on gloves when working with dangerous stuff and have the association gloves = danger.

Gloves can sometimes be dangerous. Dont go near burners with gloves. They melt with your skin.

Gloves are often unnecessary. When the substance isnt dangerous on skin contact, there is no reason to wear gloves. Chances are you get some of the substance on your glove and dont care, distributing it evenly everywhere in the lab.

Gloves can combust when they come into contact with nitric acid.