Most engine failures are not time critical - you want to take the time to make sure you're doing the right thing. For example, it's been known to happen that the crew shuts down the wrong engine (it's even happened during a Boeing 757 flight test - I had a good buddy on board who commented that "it got a little tense"
- fortunately they were at ~30k and had time to recover).
Read the those instructions as 'take your time and get it right'.
