would you have noticed? probably not.
during molt, crustaceans are extremely
vulnerable to predation, being soft & squishy,
so to survive it (some don't), they find a hideout
until the molt is complete. in 30 years, i've witnessed
1 skunk & 2 CBS molts.
many shrimp molt within a week of being placed
in a new tank for some reason, after that, they (mine)
average a molt a month, usually after a water change.
BTW, females can only be impregnated when soft,
& both sexes stand guard while the other molts
(in mated pairs, a.k.a. CBS) & i leave the molt in the tank
as some shrimp will consume the castoff for minerals.
JMO/HTH