Depending on what core workouts you are doing, i dont recommend doing abs every day. If you are doing some basic things like kegel, or standing on one leg and some other very light postural work, those can be done daily, because you are trying to get muscles to fire. but stuff like pilates and tougher ball work should be done every other day as those will definitely challenge your muscles much more.

having had all my abs now cut through from my surgery, and as i am sure anyone here who has a c-section can also agree, abs are incredibly important from simple movements like bicep curls to big movements like squats. if your abs are too fatigued from a hard workout, they can't engage properly and you can injure yourself when doing something non ab related.