Getty Images Grayson Allen

Some people live life with the glass half full, and others with it half empty, but pretty much everyone fills out March Madness brackets with regret.

After four wild days, the NCAA tournament field has been cut to 16. Perennial heavyweights Villanova, Duke and Louisville are gone, the ACC lost eight of its nine participants and the Big Ten is somehow surging with three teams still alive. You can't predict this stuff. But you can torture yourself with second-guessing. Northwestern kid, take it away.


Why did I pick the defending champion to go so far?

Elsa/Getty Images Villanova Coach Jay Wright

What a trap. Villanova was the No. 1 overall seed, but no defending champion has surpassed the Sweet Sixteen since Florida repeated in 2007. This year's Wildcats, minus Ryan Arcidiacono and Daniel Ochefu, didn't have a chip on their shoulder like the 2016 team did. The road to the Final Four in the East Region included too many roadblocks. A wrongfully seeded, hungry Wisconsin team and a rejuvenated Florida lined up in front of Villanova. It just wasn't going to work.

Why did I think Duke was actually good?

Gregory Shamus/Getty Images Grayson Allen Of Duke

Duke, the preseason No. 1, was down and out in January. The Blue Devils slipped as low as No. 21 in both the AP and Coaches Poll, dropping four of their first seven ACC games. As the No. 5 seed in the ACC Tournament, Duke rallied to win four games and the conference title in Brooklyn. Duke almost made it back to New York City for the East Regional, but its vulnerabilities proved too vast in Greenville. Coach K's crew was tripped up in the second half of the second round by South Carolina. Long story short, if Duke isn't convincingly a top team, never take them to the Final Four, for your own sanity.

Why did I not think Michigan was actually good?

Joe Robbins/Getty Images Michigan Basketball

For the exact opposite logic of picking Duke, you probably didn't pick Michigan because you thought its Big Ten tournament championship was a fluke for a mostly average regular season. Maybe you didn't pay attention to the fact that from Feb. 7 to the start of the NCAA tournament, Michigan went 10-2, losing only in overtime at Minnesota and on a buzzer beater at Northwestern. Michigan is 2011 UConn, and Derrick Walton Jr. is Kemba Walker. Reeling Louisville, loser of three of five before March Madness, was a sitting duck for the Wolverines.

Why did I forget Xavier was a legit team?

Rob Carr/Getty Images Xavier Basketball

Xavier opened the season as the No. 7 team in the nation and remained in the AP Top 25 until the last week of January. The Musketeers may be the country's streakiest team. Of their 13 losses, 11 came in a two-game losing streak, a three-game losing streak and an ugly six-game losing streak. But now, it looks like Xavier, a No. 11 seed, has its winning mojo back. Trevon Bluiett, who has 50 points in two games, is proving to be one of the deadliest players in the tournament. In a fairly inexperienced regional with Gonzaga, Arizona and West Virginia, Xavier's work may not be done yet.

Why did I take Virginia again?

Mike Ehrmann/Getty Images Virginia Basketball

You are helpless. No, just kidding. Kind of. UVA has easily been the most underachieving team in the past four NCAA tournaments. As a No. 1, a No. 2 and a No. 1 seed the past three Marches, the Cavaliers had just one Elite Eight appearance. This year, Tony Bennett's team were a No. 5 seed. Sweeping Louisville, winning at Notre Dame and beating UNC were cover-ups for losses at Pittsburgh, at Syracuse and at Virginia Tech. The Cavaliers won in the first round against UNC-Wilmington and got romped in the second by Florida, 65-39.

Why did I let the conference narrative own me?

Al Bello/Getty Images Florida State Vs. Notre Dame Basketball

It's too easy, that's why. One short week ago, the ACC was the darling of the selection committee, earning nine bids and having Syracuse fall just short. Going into the Sweet Sixteen, only regular-season champion North Carolina remains. That doesn't necessarily mean the league was worse than we believed. The NCAA tournament is about matchups, and the ACC ran into individual hot teams like Michigan, Xavier and West Virginia, and teams playing de facto home games -- Florida and South Carolina. Let this be a lesson for next year: don't just pick a team because its conference has cumulative strength. Of course, UNC can still win it all.

-- Follow Jeff Eisenband on Twitter @JeffEisenband. Like Jeff Eisenband on Facebook.

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