DF lockout on Pre-made party

I partied with 3 FC mates and queued as for my Expert roulette. As soon as we got in we noticed we had 1 tank 2 healers and a Blm. Realizing our mistake, we decided to back out; I backed out and then had the Lockout time.
They were fine however, As a result i was locked out from achieving my daily roulette bonus...which is my fault for leaving it till so late in the night.

When did this change?
Is it because I was in the Expert Roulette?
Is this just some method to prevent players from doing something else?

I am not really upset, i just want to know why it happened.

Thanks

I think they added it a few patches ago, I don't remember reading a reason, but if I had to guess, they probably did it to prevent a full party of 4 queueing for the roulette then leaving if they got a dungeon that they didn't like.

It came in with patch 2.3, and only applies to roulettes (for pre-formed parties):

Quote:

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When joining Duty Roulette as a party, abandoning the duty within the first 10 minutes will incur a penalty.
* Only the first player to leave the instance will receive a penalty.

Parties containing one or more members who have been penalized for abandoning a duty will be unable to register for duties via the Duty Finder.

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