There are historical and technical reasons for this that aren’t particularly important, but ultimately it’s an indicator that the class is a blueprint generated one (“BP_” notwithstanding since that’s not required).
It also shouldn’t matter. You say “I can’t compare this class with desired”, so I get the feeling that you’re trying to get the name of the class and compare it against a known specific name? If that’s the case then the solution is that you shouldn’t be doing that.
Either you should be compare it using the ‘IsA’ check or an ‘Equal’ node with the result of the ‘Get Class’. The ‘IsA’ check is usually better since that will also return true if you introduce a new blueprint that is parented to BP_Human (BP_Boss or something), but ‘Equal’ can be fine if you really only want an exact check.