To build a great company, it’s important to have strong executives leading the sales organization. But just as in the military, talented top officers can’t make up for weakness in the ranks of frontline leaders, the mid-level managers who are vital in driving day-to-day sales performance. “In any sales force, you can get along without the vice president of sales, the regional sales directors, and the training manager,” a sales leader once told us. “But you cannot get along without first-line sales managers.”