What is the central concept of 'skin in the game' as described in the context of insurance?

Why do insurance companies implement co-payment clauses in their policies?

What is a potential drawback of agreeing to a co-payment clause in a health insurance policy?

How do room rent restrictions in health insurance policies impact policyholders?

What is the main point the author is trying to convey regarding co-payment and room rent restrictions in health insurance?