Those systems are almost universally oversold. If someone truly had a method to guarantee consistent profits from sports betting, they wouldn't need to sell it to random people online—they'd just use it themselves and become incredibly wealthy. Most of these systems rely on aggressive bet progression or staking plans that temporarily hide losses. The real danger is that you eventually hit a losing streak and suddenly you're risking massive amounts to recover small previous losses. It's a trap that catches experienced bettors too, not just newcomers. Treat anyone claiming guaranteed returns with extreme skepticism.