I don't understand this question. Are you asking for examples of why people think their support is bad? Or are you actually asking WHY their support is bad (Kind of a silly question...because they have bad support people, that's why...lol)?
Back when I cammed on there, they were known for constantly answering models' questions with the same pitiful copy/paste responses of "You need to get an i7 processor (Um...and what about when we do have i7? What are you gonna blame it on next, Streamate? Lol.)." In public chat, we had to answer so many member "But how do I...?" questions, because I guess SM did a shit job of making things easy/clear for them too.
Models still have to explain to members step-by-step how they get their videos they tipped for. SM has it to where a model can't even message a member first...he has to initiate the messaging conversation in order for her to reply. A lot of members don't even know this, which is why some of them complain "I tipped for videos yesterday, and didn't get them." Dude probably didn't message the model.