In your posted pictures, yours is most curved because it is limp and not hard.

But in general, cocks have three chambers inside of them, that have tissue that will take a lot of ****. This blows the chambers up like a balloon. A cock has one on each side and one on the bottom, which is a little smaller. To be arrow straight, each chamber must be exactly the same length. If one is slightly longer or shorter then it causes a bend.

for example, if the bottom one is slightly longer than the two above it, the cock will curve up. If the left one is slightly shorter than the right one, the cock will bend to the left.

They all work the same way, and given the odds, it is very likely that a cock will have a bend.

That's what happens when you jack off too much with just one hand.