Sempiternity
Smash Lord
Well, most of the time, a good player won't let Ness even pull off his Up+B, because Ness should be hit while doing it, or have his thunderball thingo blocked. And if Ness is out of range while performing the Up+B, he'll be so far off the stage, that not many options are available after the Up+B ends (grab edge, or land on stage next to edge). Both of those scenarios are easily punishable since Ness spends so much time in free fall or has tremendous landing lag.
Link at least has somewhat decent priority and weird hitboxes to help him recover.
Sure, if nobody's around to edgeguard, then Ness wins, bar none, but there's a really good chance that if you're playing Smash, you're playing against somebody else.
TL;DR
Ness is just too easy to predict and punish. Any good player will not let a Ness back onto the stage. Hell, there's even room for a few mistakes in the process of edgeguarding a Ness, and still pulling off the KO.
Try this out: go on Kaillera and play a couple matches as Ness, and you'll soon see why he's ranked so low.
Link at least has somewhat decent priority and weird hitboxes to help him recover.
Sure, if nobody's around to edgeguard, then Ness wins, bar none, but there's a really good chance that if you're playing Smash, you're playing against somebody else.
TL;DR
Ness is just too easy to predict and punish. Any good player will not let a Ness back onto the stage. Hell, there's even room for a few mistakes in the process of edgeguarding a Ness, and still pulling off the KO.
Try this out: go on Kaillera and play a couple matches as Ness, and you'll soon see why he's ranked so low.