A triggered ability is considered to have triggered even if it was subsequently missed. Effects that count or restrict the number of times that ability can trigger will count the missed one.
§ 702.2.d Tournament Rules PDF (officieel)
§ 702 Game Play Errors
§ 702.2 Missed Trigger [No Penalty]: The accountable player for a triggered ability doesn’t demonstrate awareness of the trigger before the first time it would have an observable impact on the game.
