Alvin Gentry was there for the Seven Seconds or Less (SSOL) Phoenix Suns under Mike D'Antoni. After the franchise tried and failed to reboot as a more traditional team in 2008 under Terry Porter, it was Gentry who took the reigns. Then, the mantra became 12 seconds or under. The team was just as fast, averaging 95.3 possessions in 2009-10 compared to 95.9 in 2004-05. Under Gentry, the Suns didn't shoot as many 3-pointers but got to the foul line much more often. Gentry's 2009-10 team was even more efficient than any D'Antoni coached squad.
All of these teams had fatal flaws and usually that flaw was generally called defense and rarely expanded much upon. If further analysis was deemed necessary, standard NBA cliches like "Defense wins Championships" or "they were soft" were tossed about. Those teams were actually pretty decent at defending. They held opponents to an effective field goal percentage, below league average, while rarely sending them to the foul line. Digging deeper, the real reason is clear.
The Phoenix Suns could not get enough stops.
Stops require one of two things; a defensive rebound or a forced turnover. Simply forcing opponents to miss shots is not enough if the rebound cannot be corralled. The Suns regularly struggled in these two areas. Here is a look at the Four Factors on defense for the Suns under D'Antoni (2005-2008) and Gentry's first year (2010). The middle of this table, turnover percentage (TOV%) and defensive rebounding percentage (DReb%), is where an NBA defense actually gets stops.
That's a whole lot of ranking at the very bottom of the league. The Suns could defend opponents and force misses at an above average rate while also rarely fouling. Two critical components on defense. They could not finish the job and end possessions by either forcing turnovers or collecting defensive rebounds.
Omer Asik is the best possible answer to create more stops.
Some, here in the comments, on other websites, on Twitter, and elsewhere have said that Omer Asik is not an elite rebounder. This statement is false. Asik ranks as one of the best rebounders in the history of the league.
The list of players who collect defensive rebounds at a higher rate consists of Dennis Rodman (Hall of Famer), Dwight Howard (active and unavailable), and Bill Walton (Hall of Famer). That's it. Asik is not piling up stats while not helping the team in this regard either. When Asik is on the court the Pelicans posted a 77.7% DReb%, good enough for a top five mark in the league. Otherwise, when Asik was on the bench New Orleans was a bottom three defensive rebounding unit, snatching just 72.5% of available defensive rebounds.
Asik's ability to single-handedly swing the Pelicans from a terrible defensive rebounding team into an elite one surely played into Gentry's evaluation. One listen to a typical Gentry interview or press conference and he will drop advanced statistics and analytics such as the catch and shoot percentage behind the arc. Gentry digs into this stuff and believes it is valuable. That Asik's contract came in even cheaper than originally reported also plays into the value he will provide.
Offense is sexy, and significantly easier to analyze and digest. Defense and rebounding, half the time players spend on the court, is dismissed unless something goes horribly wrong. Omer Asik is the bulwark to avoid such a calamity.