BB shocks vs normal shocks

[Lowie]

as in the title, actually ...
at first, as not being blessed yet, allready, with a lot of rc-knowledge, I thought Bigbore shocks were an improvement because of the bigger volume.
I thought they were less critical as for setup. As I also thought that a proper set of shocks with just the correct setup: oil, pistons, springs .. would do as well as a regular shock.
But it seems that sometimes drivers that actually have the BB-shocks still use the regular ones.
Thus I understood that in certain conditions BB were not the best way to go

soooo .. thus my question: what are the differences between BB and regular as in in which conditions should you use BB, why ... and when could regulars be better, for what reason.
If this has been explained elsewhere, sorry and please then just point/link me in the correct direction.
thx in @vance