A lot of laptops have this problem. No brand is immune to it.
Problem usually comes down to the connecter that the manufacturer decided to use.
Usually a heavy inflexible cord mated to a dainty plug.
If that is your issue take a run to Radio Shack and see if you can pick up a more robust connector and replace it. Not always an option due to space constraints inside the box but worth looking into.
G4 cord in white and HP cord in black. Note the cable thickness compared to the plug.
Note barrell around G4 plug that takes the stress off of the connection. HP always feels like it'll snap if not handled gingerly.
Other nice thing about the G4 plug, it unscrews so you can get to the internals of the plug without having to cut through that molded plastic sleeve.
Makes fixing them easier if it comes to it.