It is something that sounds appealing at first blush. You go on a website and, "Bet," how much weight you will try and lose and how fast. It might be motivating and you can win money! It's a gamble, however, and when you gamble the odds always heavily favor the, "House," or in this case the for-profit company you're giving money to. I keep seeing ads for sites like, "HealthyWage," or, "Dietbet," and while they sound like a fun way to lose some pounds and get some cash, there is always a catch. With these sites there are multiple, "Catches," actually. First, even if you lose the weight they take a huge chunk of fees and will give you a tax form if your wager was above certain thresholds. There are no refunds even if something out of your control occurs (like an emergency hospital visit or something). These apps and sites are for-profit, so in the end, they want you to fail in the same way a casino would prefer you don't leave with more money than you entered with.
I get why these sites sound good--I have often struggled with my weight and am currently trying to eat better and be more active. That said, I'm not going to bet on whether I can lose the weight and act like it motivates me to try harder--especially when even if I do succeed the reward is incredibly minimal. The best reward for me trying to get healthier is just that, getting healthier. Plus, if I really want to bet on something I think the Saint Louis Blues have better odds of winning a game than me melting off the pounds quickly even if I am walking more. It's a process.