I don't get your point at all on this topic. What do you mean with "servers decrease"? Would you mind elaborating with what you said?
As for the lags that you're talking about, then this is server sided problem. There might be some servers which their location are too far and it makes hard to communicate with the server thus leading to huge lags. Usually they are marked with red in the Latency bar so you can notice which server is playable without experiencing lags or not.