All tournaments on Total Trivia have a scheduled time to end. However, to keep things fair and fun Total Trivia utilizes a feature we call Overtime.
When a shopper takes the lead in a tournament they will be permitted to finish their current round. When you are in the lead you can't start a new round. A shopper may only play again once someone takes the lead from them.
Once a tournament is within 3 minutes of it's end it moves into overtime mode. Overtime means that two minutes are added to the clock every time someone moves into first place. This is intended to allow all shoppers a fair opportunity to re-take the lead once someone passes their score.