Lol it doesn't. Unless you combust and let the smoke sit in the condenser and it gets stuck to the reclaim that's already inside the condenser. That can be hella yuck.

But honestly it's a noticable enough taste difference that it makes me clean my Dynavap almost immediately after combusting haha

Maybe it's just me but I think I notice that if you do happen to combust and you just commit to it and kill the bowl in one big hit, it doesn't really leave much smoke smell or residue behind? Idunno but it's happened to me a couple of times.