It's like roulette - the house odds may only be 5% but they're 5 % every single spin of the wheel. Your 95% return per spin means you actually win 0.95 to the power x, where x is the number of spins you play for. After 20 spins, you're down to 35% of your original stack.
or you could be up 1000% because you got lucky after betting it all a couple times.

that 5% doesnt mean that you are down to 35% after 20 rolls, it means that over hundreds of thousands of hands, you will be down an average of 5% a hand.