Because one dps not accepting might cause a whole group to drop out of DF. If you're queuing with friends and you're afk or stucked in loading screen, they have to queue manually again.
So one withdraw and you might have to search for 8 ppl again, while also (i suppose) the game might reorganize.
E.G. it's possible to allocate 12 of the 16 left players to five different queues to fill them up,.
Leaving 4 players waiting for fill up or to be distributed to a fuller queue.
So less waiting for 120 ppl, while four sad ones have to wait longer.
I don't say that it works this way, just showing that the system can be more complixated than expected.
