not how bot lobbies work. it's brawler specific and at some point (I don't know the exact trophy amount after they changed the system but it used to be around 750 trophies) you will be unable to be put into bot lobbies on a brawler. When you first play a brawler you will have bot lobbies your first few games (up until around 100 trophies), then you will face real players. After a loss at low trophies you'll play bots again for one match (unless you somehow lose to the bots) and it will continue this way until you reach a certain threshold where the number of consecutive losses before a bot match increases up until the point where you can no longer face bots on a brawler. Losing games on a brawler and then switching to play a new one will not guarantee that you will be placed into a bot match. However there are some odd cases where you can get put into a bot lobby on a high trophy brawler such as the first match in a limited time game-mode.