Most have ferrules on their cues but jump from tip to shaft ignoring what can be a very important piece in between. I redid an even gross of cues for a pool hall. Over a hundred of the ferrules twisted off with a firm grip. Every one of them without exception had blue chalk build up between shaft and ferrule.
As a general statement, the closer to the cue ball the more important a component is. However, that is assuming all components are decent. If you have one really bad component it will outweigh all of the rest while a great component can be lost if there are other mediocre components.