Kevin Brockway shared statistics on coaching records in games decided by five points or less and found a lot of variability.
The implication is that coaching makes a big difference in "crunch time." What we would want is to look at what transpired before or what outcomes occur (for example) when games are within four points with 'X' time left in the game (e.g. four minutes). For example, a team could trail by twelve with eight minutes left, narrow the score, but not finish. Or a team could blow a lead like Memphis did in 2008 to lose the NCAA final to Kansas.
What sequence of events causes teams to win or lose close games? How can players and coaches troubleshoot and stop this from happening?
In the NBA, a lot will depend on your 'closer'. Having a Lebron James would help, but even Lebron's effectiveness depends on how he gets isolation, being more effective off a pass.
But most coaches can't access statistical depth and breadth or have a superior closer. What can the proletariat do to compete better (or win) close games? It's a copycat world.
Score more points in transition. Golden State led the league in 2014-2015 and Houston was second.
Score from the perimeter (3s). Golden State, Houston, and Cleveland led the league in scoring from international waters. Maybe it shouldn't surprise that the Warriors were near the bottom of the league in scoring (percent of points) on free throws. It's hard to pile up points on threes and shoot lots of free throws, too.
Deny points in transition. It takes discipline and effort to limit points in transition. The Celtics led the league in allowing fewest points in transition, not surprising that a Brad Stevens team would play smart.
Limit points from the perimeter (3s). Golden State and San Antonio both finished in the top five in points allowed on threes.
Be more efficient. The Clippers, Warriors, Raptors, and Toronto were among the leaders in offensive efficiency.
How about some practical advice?
Relentlessly encourage play POSSESSION by POSSESSION
Practice PRESSURE FREE THROWS
Improve scoring in key (e.g. After Timeout - ATO) situations (such as baseline out of bounds - BOB - and sideline out of bounds - SLOB) situations. Portfolio of "winning plays" in critical situations.
Have offensive and defensive DELAY GAMES.
Sucess in close games is just one measure of overall team and coaching effectiveness. Good players and coaches want to succeed in every situation and adding value should be both our vision and mission.