You face a long sand bunker shot.
Your ball landed in the sand bunker near a high lip and to make matters worse, it is also on a downhill lie.
Your ball lands in an island of grass in the middle of a sand bunker next too the green or in a cushioned greenside rough.
Your ball is sitting up in a greenside bunker and it has a high lip to it.
It is windy out and you find your ball on a downhill slope in the sand.
You try using your sand wedge and end up skulling the ball when attempting to hit off of a thin layer of sand over hardpan, especially if the sand is wet, or scruff. This is because the ball bounces off of the flange of the sand wedge and you end up blading or chunking the shot.
Your ball lies in hardpan composed of hard-packed sand or dirt such as greenside bunkers where the club can penetrate the sand.
The ball is sitting in the front lip of the sand trap.
You have a buried or plugged ball in the sand trap.
Your ball is in a sand bunker and you must hit past a tree in order to make it to the green.