One basketball proverb you used to hear was that coaches preferred to start defense and bring offense off the bench. I don't know whether that is or ever has been true, yet it has always stuck with me, probably because I've always had a soft spot for instant-offense threats.
Instant-offense players are a different species than that of the sixth man, though the two jobs often overlap. Not every team has such a player. The historical prototypes are players like World B. Free, who began his career as an off-the-bench volume scorer on high-powered Philadelphia 76ers teams, and Detroit Pistons great Vinnie "The Microwave" Johnson, whose nickname stemmed from his penchant for quickly heating up off the bench. Players like these can carry a team for games at a time, and yet they don't always work well with others. Because they can provide offense for reserve units that lack scoring, or can inject action into the sputtering offense of a starting unit, the very qualities that work against them in a starting role make them invaluable as reserves.
Sometimes the ego that drives an instant-offense player causes him to resist the role. Players want to start. Knicks guard J.R. Smith won the NBA's Sixth Man of the Year award just two years ago and very much falls into the Free-Johnson mold -- though in reality Smith isn't a typical anything when it comes to being an NBA personality. Smith has never really grasped the importance of the role, always stating a preference for starting. Even Clippers guard Jamal Crawford, one of the more soft-spoken and thoughtful players in the league, will admit to a preference for starting even if he knows the sixth-man role is the one for which he's best suited.
Crawford is one four players to win the NBA's sixth-man award twice, and he's on target to contend for the honor once again. In recent years, the award has trended toward instant-offense players, with Crawford, Smith, James Harden, Jason Terry, Leandro Barbosa and Ben Gordon among the winners in the past decade. According to basketball-reference.com, there have been 33 seasons since 1979-80 in which a player qualified for the scoring title while meeting the current criteria for sixth-man award eligibility and also averaged at least 22 points per 36 minutes. That's less than one per season.
This season, there are six such players.