Pros of having a shoggoth maid:
-Protoplasmic, can change her biology however she please for certain purposes
-Obedient -depends on which breed she is- the original breed was obedient through mind control- while the later breed was bred to be obedient
-Very talkative, can't bored
-Can build you a city and a statue of you that lasts for billions of years

Cons
-Has the potential to rebel against you and kill you
-You need to be an Old One to control her
-If she rebele against you, the only way to neutralize her is by using Old One technology
-Very large and high maintenance