Why is static rope preferred over elastic/dynamic? (Partial)

[PreCambrianBliss]

From what I can find, dock lines are thick, smooth, soft, and floppy which I assume makes knots tighten down easier. They are typically nylon and are somewhat elastic. Static climbing rope however seems tougher and not as flexible, which makes me worry that my knots wouldn't cinch and bind how they're meant to when load is applied.

Everyone says you only want static rope, but why? Can a bit of stretch really make a difference

 

[jwordz]

From what I can find, dock lines are thick, smooth, soft, and floppy which I assume makes knots tighten down easier. They are typically nylon and are somewhat elastic. Static climbing rope however seems tougher and not as flexible, which makes me worry that my knots wouldn't cinch and bind how they're meant to when load is applied.

Everyone says you only want static rope, but why? Can a bit of stretch really make a difference

no idea but a quick search about syatic rope shows that static might stretch 5% vs 40%