Quote from IShopAtPublix:
I am going to be sticking with 50:1 and not 400:1, 200:1 or 100:1.
No, whatever you think you've learned hasn't actually happened yet. 50:1 means you can only lose 1% on something before you lose half. That means you'll be down for sure that much at some point.
Or you'll get lucky and think you know what you're doing.