The greenside bunker is the only shot in golf where the player is, in the literal sense, trying not to hit the ball. Every other shot in the bag is a contest between the clubface and the back of the ball. The bunker shot is a contest between the clubface and a patch of sand an inch or two behind the ball, and the ball comes out only as a passenger, carried on the cushion of sand the club has thrown into the air. The amateur who walks into a bunker and tries to hit the ball is fighting the one shot in golf that does not want to be hit. The sand wins that fight more or less every time.
What the club is actually doing
The reason the standard bunker shot works is the bounce on the sole of the sand wedge, that rounded flange that sits below the leading edge. When the face is open, the bounce becomes the lowest point of the club, and it allows the wedge to skid through the sand rather than dig into it. The shot is a splash, not a dig. The club enters the sand behind the ball, slides under it, and the sand does the lifting. The ball rides out on a thin layer of sand and lands soft. Done correctly, the player never feels the ball at all. There is only the thump of the club into the sand and, a beat later, the ball settling on the green.
The amateur version goes wrong at the setup, before the swing has even started. The player who is nervous about leaving the ball in the bunker does two things that guarantee the outcome they are afraid of. They square the face, which takes the bounce out of play and turns the wide, skidding sole into a sharp, digging leading edge. And they try to lift the ball into the air with the hands, which steepens the angle of attack and drives that leading edge straight down into the sand. The club digs, the sand grabs it, the clubhead stops, and the ball travels four feet and stays in the bunker. The player has done exactly what the shot punishes, which is to attack the ball.
The setup that does the work
Most of the bunker shot is decided before the takeaway, which is the good news, because setup is the part of golf the amateur has the most control over. Open the face of the sand wedge first, laying it back so the bounce sits underneath, and then take the grip. Doing it in that order matters. A player who takes the grip first and then tries to twist the face open will have the face square again the moment the hands return to neutral through impact. The face has to be opened and then held there by the grip, not opened as an afterthought.
From there, widen the stance a little, work the feet down into the sand for a stable base, and let the weight sit slightly favouring the lead side. The ball goes forward in the stance, roughly off the lead heel, which encourages the club to enter the sand behind it. The single most useful thought from that position is to pick a spot in the sand an inch or two behind the ball and commit to hitting that spot. The ball is no longer the target. The sand is the target. A player who can move their attention from the ball to the sand has already solved most of the shot, because the swing tends to deliver the club to wherever the eyes are looking.
The swing, and the part nobody finishes
The swing itself asks for two things the nervous player tends to withhold. The first is speed, and the second is a finish. The instinct in a bunker is to decelerate, to be careful, to baby the club into the sand because the green is so close. Deceleration is the enemy of the splash. Sand is heavy, and the club needs enough speed to carry through it and out the other side, throwing the sand and the ball onto the green. A useful rule of thumb is that the bunker shot needs a swing roughly twice the length the same distance would need from grass, precisely because so much of the energy is spent moving sand rather than the ball.
The second thing is the finish, and it is the part the amateur abandons most often. The club has to keep moving after it enters the sand. The swing that stops at the ball, or stops in the sand, is the swing that leaves the ball in the bunker. The swing that finishes, with the hands ending up somewhere around shoulder height and the chest turned through to the target, is the swing that splashes the sand out and the ball with it. A good practice habit is to draw a line in the sand and rehearse splashing it out with no ball at all, until the sound and the divot become familiar. The shot is far less frightening once the player has heard a good one a few dozen times.
The shot that lowers the score
None of this is the high, soft, one-hop-and-stop shot from a Sunday broadcast, and it does not need to be. The goal for the amateur is simpler and more valuable, which is to get out, every time, to somewhere on the green. The player who walks into a greenside bunker confident of two-putting from it has removed one of the genuine card-wreckers from their round, the double or triple that arrives when a bunker shot stays in the sand and the next one does too. Open the face, aim at the sand, swing with speed, and finish the swing. The ball is along for the ride, and the sooner the player stops trying to hit it, the sooner it starts coming out.