To maximise profits, you need to maintain a high turnover by placing many bets. When placing a high volume of bets, there are two ways of distributing that volume. One way is to use 1-3 bookmakers at any one time and placing bets on as many opportunities as you can, placing on all leagues, low percentage edges, and games that start more than a day ahead. Placing on low percentage edges and games that start far in the future will increase your variance. The optimal solution is to spread the volume throughout bookmakers, while only placing bets on the best opportunities on each book. For high volume traders, this can't be stressed enough. By using 5 or more bookmakers, you can consistently place on the best opportunities, whilst maintaining a high volume and a lower variance by placing on higher edges, games closer to game time, and stick to recommended leagues. By doing this, your account on each bookmaker will last a lot longer.
In our community, we've had users running through bookies, one by one. After signing up on a bookie, placing 200+ bets the first 24 hours, they're shut out, and that's that. Bookmakers are consistently trying to shut out winning players, and there are almost no losing players that put in that kind of volume, making you too easy to find and shut out.
I understand that signing up to many bookmakers and keeping track of the websites and money management is a bit tedious, but if you're here to make some serious money, it's definitely the way to go. Personally, I'm using a password manager called Dashlane to keep track of all the passwords in a secure way.
Goodluck and happy trading!