Simple question: How many dicks have you sucked in your life? (An estimation is fine.) Did you finish the job every time?
There's no way I can keep track any more - probably about 50 by now. As for completion - well, not exactly, as I find even the idea of semen inside my mouth gross - and that includes my own (I've forced myself to swallow my own semen a few times, but felt nauseated by it on each occasion). However, I've always made sure of giving full satisfaction in one way or another. To me, Oral is just part of Foreplay, and not a sexual act in itself.