spawn camping relies on the enemy making mistakes.Fair enough, but I still think that the concept of spawn camping itself is not flawed.
1) campees allow themselves to be distracted
2) campees don't pay attention to flank routes
3) campees don't have awareness of each other
in ranked you can kinda ignore them and go for the objective (or at least pretend you are to bait them, then hide and take them out), so it counts on the enemy abandoning the objective. SZ is more camp-friendly seeing as the playstyle is not far off from TW, but a patiently executed flank from a single member on the camped team can result in a zone reversal (dat punishment timer) and a wipe.
in TW it's easier, but it still relies on the enemy not working as a team. if the enemy is patient enough to wait til they're all/mostly alive and have a special or two going for them they can wipe the enemy out rather suddenly -- since only the last 30 seconds really matter as far as laid ink is concerned, the enemy team has ample opportunities to work out a reversal. in my case if i'm being camped, i like to tag slowly behind an obviously weak team member (who unknowingly becomes bait) and pop out at the enemies when they reveal themselves.