Swiss tournaments - "join the team"

I see there are Swiss tournaments on lichess now. This is great!
But when I check every single tourney page, it proposes me to "join the team". What does it mean? Every single organizer wants me to join his team to participate? Or how this should work?

lichess statement:
"Swiss tournaments can only be created by team leaders, and can only be played by team members.
Join or create a team to start playing in swiss tournaments."

Yeah, thanks! Also found it in descriptions...