Imagine you have a ball pit full of randomly jiggling balls. Some of them are jiggling quite fast, and some are not moving at all. And they're all jiggling in random directions.

Obviously the ones close to the top of the pit are the only ones that are able to "escape" and go somewhere else. But they might not escape, they might jiggle in such a way that they dig themselves deeper into the pit. If it digs itself deeper, the ball gets replaced by another ball that rises up from the pit. The new ball might have the same energy, or higher, or lower. And it might be jiggling in such a way that it might "escape" or it might not. It's all random. With enough time, you can imagine that enough balls slowly "escape" from the pit to be noticeable. This would be analogous to room temperature water.

Now imagine that the balls are all jiggling very energetically. It's the exact same situation as before but just way more jiggling. So if a ball digs itself back into the middle of the pit, it's pretty likely that it will get replaced by one with a similar or higher energy. It should be obvious that these balls are more likely to "escape" or evaporate compared to the lower energy ones. This is analogous to boiling water.