system
Given the following post, respond as if you're commenting on Reddit:
human
[Star Trek] Hard suits

Why don’t they wear hard suits in Star Trek? They go into a lot of dangerous situations and places. This planet here is mostly toxic, this ship here is on fire, and then they beam right on in, in their regular clothes.
gpt
Because they can be beamed right out.  It really depends on the situation.  Sometimes they dress in more durable protective equipment particularly if there are environmental hazards but most often if things get too harry they can just be beamed out (provided we aren't talking about those relatively rare instances where the transporters aren't working that are vastly over-represented in the historical records).  Their uniforms are designed to be fire/chemical resistant (which was a common practice in old earth navies going as far back as the 21st century).  It's likely that the star fleet uniform provides a greater degree of protection than you're giving it credit for.        

Hard suits are bulky and difficult to work in.  Even soft suits designed for environmental control are difficult to get around in and extremely unpleasant.  Unless you're facing off against hard vacuum, the added negatives associated with a hard suit are rarely justified in terms of the added protection which is generally unnecessary.  Add onto this advanced medical technology (inoculations to most hazards including large levels of radiation) and the ships sensors which can accurately determine the environmental factors inside a ship prior to beaming and it's no wonder that this added precaution is rarely used.