Guild Wars 2

Hello question about ESL.
Since we always see the same teams abjured , orange logo, civilised gentlemen
vermillion , apex prime

So how does these teams get qualified? seems like its always the same
There is a couple more i dont remember for now.
Is it based on ratings? how does one become pro ?

They had a tournament before the season started to see which teams would be in the pro league. Half of them were given spots based on past performances, and the other half had to fight their way in. Every season the lowest pro leaguers have to fight to keep their spot.

At the end of every season, the lowest performing Proleague teams and the top teams from the guild challenger league are in a tournament and the top players from that tournament move up to the Proleague for the next season.

Also, if any Proleague teams disband, then they’re replaced through the same tournament.