There are many good reasons to keep kitty indoors. The number one reason is to keep it safe from harm; from getting hit by cars or attacked by other animals. It also prevents your cat harming native wildlife or becoming a neighbourhood nuisance.
However keeping your cat indoors can also throw up some challenges.
Cats need to express their natural instincts. If you don't provide the proper means for that, your fur baby could end up behaving in undesirable and destructive ways.
And much more!