Currently in a Facebook group there is rather long discussion about when a trigger would be considered missed:

Andy controls Young Pyromancer and plays a Daze sits and want to wait and see if Natasha will respond, would the trigger be considered missed if:

a) Natasha pays for the Daze
b) Natasha doesn't pay for the Daze
c) Natasha plays a spell in responce to the Daze

I remember there being a discussion around the time the current missed trigger policy was released about extort and counterspells, mainly things like Mana Leak/Spell Rupture. if the player waits to see if their opponents has a response and the first time they mention the trigger is to say they are going to pay for Extort after their opponent has chosen to respond or not they are considered to have missed the trigger.

The moment the trigger is considered missed in this scenario is resolving
Daze (because the trigger should have resolved before that). Which means
that Andy needs to show awareness of the trigger before Natasha pays for
Daze or “in response” to her attempt to pay or refusing the pay. He can't
let the Daze resolve without saying although he is not obliged to point out
the trigger until Natasha chooses to allow Daze to resolve.

Therefore, in case a) he needs to point out the trigger immediately when
Natasha chooses the pay for Daze, which nullifies her choice and after the
trigger resolves, she can choose not to pay for Daze. The same is true in
case b). In case c) the trigger is still on the stack and it is not
considered missed until the resolution of Daze.


2013/12/9 Gareth Tanner <forum-7399-32fc@apps.magicjudges.org>

I cannot remember at all how we dealt with extort, though my instinct would be that the situation is a bit different in that the player needs to make a choice to pay or not which affects the amount of mana that they have available to pay for the potential counterspell.

In the Young Pyromancer case, anyway - I'm pretty much on board with David. Just waiting cannot make you miss a trigger - he could be waiting to see if Natasha has a response to the Daze, for example. Players are assumed to be acting at the first point that they can, so if Natasha plays a spell in response to Daze, she is also responding to the trigger unless she specifies otherwise - so this in itself does not cause Andy to have missed his trigger. Though he will need to say something about it as soon as it becomes clear that Natasha starts to allow Daze to resolve, in either sense.