One simple yet defining statistic that is backed up by 20 years of data - Defensive Efficiency
Defensive efficiency is the essentially the amount of points an NBA team will allow per 100 possessions. According to my research on NBA.com, I looked at the past 20 years of defensive efficiency and found that the NBA Finals match up consists of two teams that were both in the top 10 in defensive efficiency. The following is the list of the finals matchup each year since 1996-97 as well as their defensive efficiency:
1996-97: Chicago Bulls (Champions) 4th vs Utah Jazz 11th
1997-98: Chicago Bulls (Champions) 3rd vs Utah Jazz 15th
1998-99: San Antonio Spurs (Champions) 1st vs NY Knicks 3rd
1999-00: LA Lakers (Champions) 1st vs Indiana Pacers 13th
2000-01: LA Lakers (Champions) 19th vs Philadelphia 76ers 3rd
2001-02: LA Lakers (Champions) 7th vs NJ Nets 2nd
2002-03: San Antonio Spurs (Champions) 3rd vs NJ Nets 1st
2003-04: Detroit Pistons (Champions) 2nd vs LA Lakers 8th
2004-05: San Antonio Spurs (Champions) 1st vs Detroit Pistons 3rd
2005-06: Miami Heat (Champions) 10th vs Dallas Mavericks 11th
2006-07: San Antonio Spurs (Champions) 2nd vs Cleveland Cavaliers 4th
2007-08: Boston Celtics (Champions) 1st vs LA Lakers 6th
2008-09: LA Lakers (Champions) 5th vs Orlando Magic 1st
2009-10: LA Lakers (Champions) 6th vs Boston Celtics 5th
2010-11: Dallas Mavericks (Champions) 7th vs Miami Heat 5th
2011-12: Miami Heat (Champions) 4th vs OKC Thunder 9th
2012-13: Miami Heat (Champions) 7th vs San Antonio Spurs 3rd
2013-14: San Antonio Spurs (Champions) 4th vs Miami Heat 11th
2014-15: Golden State Warriors (Champions) 1st vs Cleveland Cavaliers 20th
2015-16: Cleveland Cavaliers (Champions) 10th vs Golden State Warriors 4th
* Teams in bold represent teams that made it to the finals and their defensive efficiency was outside of the top 10.
Why is this important: In the last 20 years, only six NBA teams actually made the finals with a defensive efficiency outside of the top 10. Furthermore, only the 2000-2001 LA Lakers were victorious winning the NBA Finals with a regular season defensive efficiency outside the top ten (though, a team with Kobe and Shaq back in the day were a dominant duo in their prime, creating an outlier for purposes of this argument). Essentially, since the 2007-2008 season, only two teams made the finals with middle of the road defensive efficiency, both were LeBron James lead teams that ultimately flamed out in the finals. When comparing to the Cleveland Cavaliers this season, they are currently ranked in the bottom third in defensive efficiency (23rd) while their main threats, Toronto 8th and Boston 11th have far superior defensive teams.
When evaluating the Cavs roster, they lack guards who can consistently cover other teams best shooting or point guards. Kyrie and JR are at best below-average defenders, and KK does not add any defensive presence to their team. This is a tall order to overcome in a series playing Washington with John Wall and Bradley Beal, Toronto with Kyle Lowry and DeMar DeRozan, or Boston with Isaiah Thomas and Avery Bradley. Instead, the Cavs have to rely heavily on score, rather than defense, to win games in the playoffs. Yes, the Cavs have LeBron James, but at 32 years old already logging 40 minutes a night, it is hard to imagine he elevating his game another level for the playoffs and overcoming the defensive inefficiencies of this team to make a finals appearance, let along when it all.
Conclusion: Therefore, based on historical data and current season statistics, I guarantee the Cavs will NOT make the finals based on their inability to defend at an elite level and their over reliance on outscoring opponents to win games. Though I do not know which team will come out of the East (hopefully Celtics), I can assure that the Cavs do not have the talent this year offensively to make up a relatively poor defensive group.