Interesting Go-around at Glasgow by the Emirates 777. The crew forgot to raise the gear for quite a while. Perhaps they were over-excited by the fierce Scottish weather!
Windshear, possibly?
I don't know about the 777, but on my airline's A320 fleet the SOP (one of the memory items, in fact) is not to touch the configuration until we have confirmed we are out of the shear. It's possible they had one in those conditions and left the gear deliberately.