In theory, it should be easy to make money betting on sports: you just have to be correct over 52.38% of the time (assuming standard -110 juice). I mean, flipping a coin would result in a win against the spread (ATS) half the time. So why are the vast majority of people who dabble in sports betting unprofitable long term? Surely rational beings with critical thinking skills should be much better at predicting future outcomes than literal inanimate objects?

It’d probably be cynical and arrogant of me to believe that 90%+ of people simply can’t choose the right side at a >53% rate due to judgment deficiencies and natural cognitive biases. Instead, I think it’s mainly a question of discipline. Most of the people I know who see their bankrolls dwindle typically make one or many of the following common mistakes:

1) Changing Unit Sizes

Sports betting is all about money management. If you’re a novice/amateur bettor, I highly recommend using a flat betting style (bet the same amount for each play). Please.

I think every bettor knows this deep down, but few have the discipline to always make responsible decisions with their bankrolls. The most prevalent issue probably involves overreactions to winning or losing streaks. Many bettors will grow overconfident when they go on a hot streak or win several bets in a row and begin to increase their unit size, and others will experience a brief cold streak and begin to either increase their unit size in an attempt to get back to their original bankroll (chasing losses). That’s an easy way to quickly go broke.

Think long term. That means remembering that it’s not only about making money, but keeping the money you make. A lot of bettors do the former, but screw up when it comes to the latter.

2) Making Too Many / Degenerate Plays

This one goes out to all the degenerates out there (me included, I’ll admit it!). I’ve met people who place 10-15 or even more wagers every day. Insanity! There’s no way anyone could find a sustainable material edge on that many events. Instead, it’s better to be more selective with your bets and focus on the ones that you’ve thoroughly researched and are extremely confident in. Quality, not quantity.

And yes, I completely understand the occasional urges to make degenerate plays (it’s exciting, you know?). I recently bet on the Atlanta Dream to win straight up against the Seattle Storm after 25 minutes of extremely rushed research. For context, I’d never watched a full women’s basketball game at any level prior to making that wager. I know, stupid. But I liked how the Dream’s play style (rugged, defensive, physical) matched up with the Storm (finesse, offensive, fast pace) and how the money in the market was moving in favor of the home team Atlanta. So yeah.


Other sports I don’t typically watch but sometimes “degen” on: Japanese soccer and rugby.

For those of you like me, here’s my advice for you. Because sports betting is my primary source of income, I cannot do extremely risky things that may ruin my livelihood. So I have what I call a “degen fund”, and it’s exactly what it sounds like: I keep a separate bankroll purely for my degen plays! If it gets above a certain amount, I withdraw into my main bankroll. If it goes to zero, I’d stop. (It’s never gone to zero yet though, heh.)

3) Overreacting to Recent Trends

The most important requirement for meaningful supporting data / evidence? Sample size. Large sample size.

A pitcher you’ve bet on has a terrible outing and you decide to fade his next start. A team wins their last five games and you assume they’re on a hot streak that’ll continue indefinitely. That’s nice; here comes a trap line from Vegas for you to fall for.

4) Using the Transitive Property (Incorrectly)

You guys all know the transitive property in math, right? If a = b and b = c, then a = c. If a > b and b > c, then a > c.

Well, that doesn’t always apply in sports. Just because Team A blew out Team B last week at home and Team C lost convincingly to Team B two days ago, doesn’t mean Team A will win easily against Team C today. Context matters. Personnel, matchups, home court advantage, places in standings, rankings, etc. Everything matters, and everything can change day-to-day, team vs. team, player vs. player. You’ve got to factor all of that in.

5) Not Grabbing the Best Lines

This applies in two ways: 1) not shopping for the best line/odds across different sportsbooks and 2) not taking a line/odds before it moves unfavorably. How many times have you taken a -4.5 only to have your team win by 4 points? More times than you’d like, I’m sure. I’d recommend at least having two accounts: one at a square book (such as Bovada) and one at a sharp book (like 5Dimes). For Bitcoin bettors, Nitrogen is on the sharper side.

Over the long run (hundreds or thousands of bets), extra points and reduced juice will make an extremely significant impact on your profitability.

6) Misunderstanding or Ignoring Value

Value isn’t as simple as finding a soccer team on a winning streak that is priced at high odds against a team that has lost a few games in a row. It’s about understanding what betting odds represent, calculating your own probability estimation, converting it into odds, and looking for discrepancies in what you believe the odds should be and what the bookmaker believes.

Take these two separate unrelated bets for example:

(American / Decimal)
Probability of Winning
(In Your Opinion)
Bet 1 +1000 / 11.00 20%
Bet 2 -500 / 1.20 70%

Do you understand why Bet 1 is the bet with value here even though (you think) Bet 2 has a 70% of winning as compared to Bet 1’s 20%? Again, this is all about long-term profitability, not winning one individual wager.

7) Making Long-shot Parlays

Ah, parlays. So attractive and so dangerous. For anybody unfamiliar with this bet type, a parlay is a combo bet with two or more wagers linked together. If any of the bets in the parlay lose, then the entire parlay loses. However, bettors can sometimes parlay several teams together for massive one-time payouts.

That’s right, parlays can be “get rich quick” tickets. Most novice bettors dream about hitting that 8-team parlay that pays 150/1 to instantly turn $50 into $7500. “Even if you win just one out of every hundred 8-team parlays, you’d still be profitable!”

Unfortunately, most “get rich quick” attempts only result in people “losing money slowly”. Add to that the fact that parlays don’t pay out anywhere near the true odds of your wagers, and it’s easy to see why they’re fool’s gold:

Let’s say you’re a bettor who hits on only 50% of your bets and you want to take a 5-team parlay (pays 20/1). If we multiply 0.5×0.5×0.5×0.5×0.5 we get 0.03125. That means your expected payout would be (0.03125 x $2000) – (0.96875 x $100) which equals -$34.375. In other words, for every $100 bet you can expect to lose $34.38 as compared to the expected loss of $9.09 for a single bet assuming standard -110 juice. Needless to say, that’s not ideal. So stay away from those enticing long-shot parlays!

8) Blaming Bad Luck

I believe that luck doesn’t exist. Hear me out here.

“Luck” doesn’t exist as anything but a concept. It’s just the subjective perception of coincidence (the human brain is prone to picking out patterns and erroneously assigning significance to them). Outliers can occur, but they become insignificant in the long term. For example, a coin may land on heads 35 of the first 50 times you flip it. But the more you flip it, the more heads and tails will even out.

Whether you win or lose, always rationally think about “why”. Gambling is a logical trade, not an emotional one.


loves sports, games of skill, game theory, psychology, blockchain tech, and many other things.

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