Even though Teambuilder came out like 9 years ago I was instantly able to hear the theme in my head; probably because of how absurdly long the wait times were and how often the music looped while waiting lol. We really are spoiled nowadays.
Check it out:
https://www.youtube.com/watch?v=hItcYNgvjvE&t=18s&ab_channel=frostyNinja
Teambuilder was that you chose only one role and one champ iirc. So queuetimes were horrendously long. And it was like that you got people added to your lobby through the queue and you were able to choose if you wanted to be with certain player or not. And you went into game if you found all 5 players. You were waiting the longest for support.