Bankroll management and risk management are so critical that when done wrong or not at all it can take a winning system and make it go broke.
As a young bettor, I made mistakes in this realm and it cost me. The feeling of chasing losses is inherent in most of us. As a species, it was imperative in order to survive to hoard resources. Losing any of them could mean death. This is why we have an aversion to loss that is much greater in its emotional impact than gains are.
PGA pro's make more 10ft putts for par than they do for birdie. This makes no sense since they should be the same but the reason is a bogey is a loss while a par is not. The player will be more aggressive on a par putt to avoid a loss while being a little more cautious on the birdie putt to assure no loss (a par). The result is also more double bogeys. But the players' emotion is if I lose (bogey) what's the difference if I lose bigger (double bogey). The great players manage mistakes and their risk. Tiger Woods in his prime never took an unnecessary risk while Phil Mickelson would make a bad shot worse by trying to "get it all back" in one swing.
There is no reason to take more risk just to avoid a loss. Losses are part of gambling. n order to keep yourself from chasing those loses have a plan.
1. Set aside a bankroll for the betting season.
2. Your bankroll should be money you do not need for anything else in your life.
3. Your unit size should be 1-2% of that bankroll
4. Be cognizant of the fact your parlays and or teasers on a team will open you up to more risk than your single unit size bet if you have multiple bets on the same side. Scale back so your total risk on a side is in that 1-2% range.
5. As your bankroll goes up or down you can change your unit size accordingly. This will help accelerate the bankroll if you have a winning system while giving you more time to turn around a bad run.