Of those who only played second base, that is never switched to another position to extend their career, Lou Whitaker played the longest. He was 38 when he retired and he was still an excellent offensive player and adequate in the field. He had the best final three seasons of any second baseman in history, though of course he was essentially a platoon player. Nevertheless, when he retired he was doing everything he was good at – drawing walks, hitting for power, and driving in runs. Whitaker was never that much interested in being a DH, and his personality didn't fit that role (he became distracted quite easily), which is too bad, because he could have been a fine platoon player for a couple more seasons and padded his career stats a bit. But, he'd made his money and he went home to be with his family. As a young player, Whitaker was one of the fastest players in the league, but he ran funny. As a kid he'd been pigeon-toed, and he still carried that with him a little. He had a tip-toe gate to his stride that made it seem like he wasn't running as fast as he was. A longtime teammate of Whitaker's told me that he never saw Sweet Lou work much on base stealing, and that he refused to get signs or send signs to teammates on the bases. Whitaker was talented but didn't really care much about working on the details of the game. That's the biggest difference between he and his double play partner, Alan Trammell. But in spite of not having much use for honing the details of the game, Whitaker was a great player. His raw talent was that good. Given that he ranks seventh all-time in WAR among second baseman, was the leadoff man for a World Series winner which happened to be one of the best teams in baseball history, and that his contemporaries awarded him with Gold Gloves and other honors, Whitaker deserves a hell of a lot more than just one year on the HOF ballot. We have him ranked ahead of eight Hall of Fame second basemen on our all-time rankings. But the Hall seems to have something against second basemen, as evidenced by the fate of several others, such as Bobby Grich, Willie Randolph, and even Laughin' Larry Doyle. He compares favorably to Ryne Sandberg, an almost exact contemporary. Sandberg got more hits than Whitaker (about 18 more a season), but Sweet Lou drew 24 more walks per 162 games and he did not hit in as favorable of an offensive environment. Thus, Whitaker's career OPS+ is higher. He also accumulated more career WAR and his career WAA% is better than Ryno's. But Sandberg was elected to the Hall of Fame in his third year of eligibility, while Whitaker was bumped from the ballot after one.
As someone who watched Whitaker play his entire career, and also saw Sandberg play a lot too, I say this: had Whitaker played his career in Wrigley he might have hit 300 homers, and his defense was every bit as good as Sandberg's. He also didn't stop being an effective player at the age of 33, like Sandberg did. Perception and a cable TV super station go a long way in making a Hall of Famer.