What is your procedure when a microburts is issued? How long must you stay on the ground before taking off?

I am asking because of the microbursts alerts issued out of Denver couple weeks ago and watching a Lynx plane takeoff on Runway 08 in the middle of the alerts.

Also to be fair, a United, SouthWest, and Frontier used Runway 08 for departure during the alerts. Everyone else on Tower freq declined to take off on Runway 08 or 17R and 17L. I was in shock as to why those 4 planes took off while multiple planes were going miss on runway 16R and 16L.

Thank you.