Why do golfers always advise people to keep their arms straight, when this is impossible to do?

Question

I have heard it so many times before. As a young boy teeing off "keep your arms straight". Even my own father would shout it at me. Now as a man when googling for golfing tips almost every single coach on google says the same thing, "keep your arms straight". I am however beginning to think that this is just a cliche that they are passing on, and they do not even know the meaning of it themselves, as quite simply when they tee off they also do not keep their arms straight throughout the swing. Quite simply, it is impossible to do.

Standing at six o'clock, you can really only backswing until 3 o'clock before it becomes impossible to backswing any higher without bending the arms.

So what do they mean by "keep your arms straight"? This is not good advice without explaining the entire process.

Plenty examples in of what i mean in this link

Answer 1

It's not "arms", but "arm". If you're a righty, then you keep your left elbow straight, from the start of the backswing through well past contact. Your left arm is keeping the club head open and even with the ball, so you don't end up shanking the ball left. You absolutely can do this if you have sufficient flexibility, though of course that flexibility may well be something you need to develop with time and practice. Your right arm certainly bends, but that's fine, it's the left that's keeping the club head aligned properly.

Just like in tennis, baseball, or any other sport where you hit a ball with a stick, you want to reduce the things that can change during your swing. In the case of golf, you want to keep your swing consistent - and letting your left elbow flex means the club head may close at the wrong time.

See for example this article which shows a nice example of a golfer doing this, and this article which explains the fundamentals you need to have in order to keep your left arm straight.