That’s a little vague. Can you provide specific examples?
All plugins hosted in the WordPress plugin repository need to conform with these guidelines.
https://www.ads-software.com/plugins/about/guidelines/
When a plugin is submitted for the first time then it is reviewed by a small team of dedicated volunteers (I am not on that team by the way).
Sometimes (not often) a plugin will get through that misses one of the items above. Or when a plugin is updated the plugin is changed in a way that violates one of those points as plugin updates are not reviewed.
There are 32,000+ plugins and reviewing all the plugin updates is just not humanely possible. ??
When a plugin does break the guidelines then it can be reported and the author will be communicated with to resolve the issue. That’s why I’m asking for specific details.