The short answer is "that's just how jams go."
Not everyone who sign up for a jam is able to finish, which can be for several reasons. Signed up but forgot, couldn't think of ideas, couldn't find a team and didn't feel comfortable solo deving, scope-creep got out of control, busy week so didn't have time (hi, that's what happened to me), etc etc etc.
Not to mention that projects that do get submitted aren't exclusively from solo devs - so the number of entrees inherently will always be less than the number of members.
Put it all together and a small 38 person jam might only get 9 projects submitted.
(And while I'd rather not address it tbh - some people are homophobic - while, I'd like to assume the community that has grown out of these lil' guy jams generally aren't - it's not outside the realm of possibility someone quit from this specific jam for that reason. Though if that was the case, I'd assume it was only a small minority of participants, since the previously listed reasons are typically more likely to be the cause.)
So yeah - "that's just how game jams go."
It's fine, it happens. If someone wasn't able to finish, they may have at least gotten a chance to start a new project to finish later or simply just practice for a skill set. There's always the next jam.