For the most part, recruiting is about relationships built over time. Reaching the CFP in '18 might sway a player or two who already had ND in a top 2 this cycle, but probably isn't going to completely turn around anyone who wasn't previously listing ND high. So that's part of it. Another part is that a top 15 class is pretty good. The large majority of college football teams would love to have a top 15 class. Also, rankings don't necessarily correlate perfectly with how well a team recruited. Rankings are largely raw data reviews. Some times a team has a great class that doesn't translate that well to paper analysis because its value is based on filing needs, or balance, or key acquisitions. Teams with fewer recruits tend to have lower scores, because the math is cumulative to some degree. I think most services rank based on the top 25 recruits in a class, so falling below 25 recruits costs you points. At 247, only one team in the top 10 right now with as few recruits as ND has (21). Interestingly, ND has a higher average rating per player than Clemson, who is just in the top 10 (with 27 recruits) at #9. Finally, ND is kind of tough sell. The lore and tradition isn't what it used to be (though ND's brand still has some shine). ND isn't every kid's cup of tea: cold weather, South Bend is kind of a pit, academics are serious, ND isn't as easy a sell as it used to be. Tough to compete for kids from the South and West, where most of the talent is, when sunny fun schools are in the mix.