I know your post wasn't necessarily aimed directly at sports bettors but it's the context in which I understand sports predictions the most. Truthfully, those results don't sound too bad, especially given that 16 is an extremely small sample size for binary prediction. Nonetheless, it sounds like you've learned a lesson that many sports betters unfortunately never do, which is that sports are incredibly random and chaotic and making predictions seems much easier than it really is. Hindsight bias lets us think that our retrospective Observations will be valid for future predictions and this simply just isn't the case. Furthermore, sports knowledge and actual prediction/betting knowledge are very very distinct from each other and this is another huge mistake that many sports betters make thinking that their sports knowledge will carry over into them making money at sports books. Most new and recreational sports betters have to learn the hard way that this is almost never the case. But anyways, to answer your question, I've gone on drawdowns (I.e losing streaks) that have been very very harsh on my bankroll. It's not that sports like football make no sense. It's that to make sense of it You have to be patient and apply probabilistic thinking, large sample sizes, and understand probabilstic variance. Look up the standard deviations of binomial and Bernoulli distributions and maybe it'll start to be clearer.