Roulette strategy

I lost my 25$ with bad system. It's about betting on the one of the colors(black or red) and the winning chance is 50/50. So if you bet 1$ on black and the red came out the you bet 2$ on same black. If you lose again 4$ and so on. I was betting 0.5$ each hand and lost my 25$ very quickly. You have to realise that there is same chance to red come out after 10 spins as it after 2 or 3 in a row. Because roulette table has no memory. Personally i saw 14 reds then 0 and 12 black in a row in online casino. So you can lose your all money if you use this strategy.

Let' count if you bet 0.1$ on black and there spins 14 red in a row.
0.1$ + 0.2$ + 0.4$ + 0.8$ + 1.6$ + 3.2$ + 6.4$ + 12.8$ + 25.6$ + 51.2$ + 102.4$ + 204.8$+ 409.6$ + 819.2$

You lose 1638.3 $ in total. Do you have funds like that? Yes its not possible to lose if you have all world's money.

There is a great risk and not huge profit. This tactic refund every lost stake. For example if you bet 1$ lost then 2$ lost and then 4$ and won. That means you won 4$ and lost 3$ so you profit is equal to your first. And that also means that you are betting 819.2$ as i mentioned before just to make your 10 cent profit. It's not smart i think :)).

I now playing with almost the same tactic just i double my bet four time and no more. Also i am not betting on colors. I mix it with pair and unpair, high and low, sometimes betting on 1st 2nd 3rd section of numbers.