Health care deductions on your pay stubs?

You all see how much health care insurance deduct from your pay checks, chances are you will not even use that deductions that year or next year, why can't you get any money back?. With all that money deducted from your pay checks, it seems your insurance will only cover 50% or less and you end up paying the rest 50%. Shouldn't they give some money back if they can't cover you 100%. For instance, I have this insurance, I was working for FIVE years, which means the insurance were collecting and deducting money from my pay check for FIVE YEARS. That is $ 25.00 per pay check. 1815x25 You do the math. That is a lot of money. I never used my insurance, never went to the hospital. Yesterday, I went in for a dental work, and I was simply told that my insurance covers only 50%. Where did all that money went that I never used for anything?. What is going on here?
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That's the way insurance works. You keep paying until you need it, and then you pay more because they don't cover 100% of what you need. And you're lucky to be paying only $25 per check. My premium is $200 per paycheck.
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