You actually roll low in GURPS, so 8 is a success if the target number was 10. Your margin of success was only 2 though, so it wasn't that great a success, so I guess saying it was a bit rubbish makes sense.
Of cause, if you're jumping onto moving ships and similar, then GURPS has advantages like Luck and bought success rules specifically for over-the-top against the odds heroics - so even if you'd failed the roll nothing would've stopped you from dropping a few cp to succeed anyway (assuming the GM is using those rules).