Find your 'bell cow'
On the ranch, the herd will follow along behind the one cow with a bell around its neck.
Source: Sales trainer/consultant Kevin Davis
Many salespeople, especially those with less experience, emulate the example of the team's "bell cow". So, it's important for you, as a sales manager, to study your team and identify who is the bell cow (informal leader)?
Next, what example is your bell cow setting? Does he/she display excellent work habits? Or, does he/she simply sit back and "milk" the best territory? The example of work ethic and attitude that your bell cow displays for the team is, perhaps, even more important than the example you set for the team.
Hopefully, you already have a few players capable of stepping up. If so, talk to them. Help them see the importance of their success example, and ask them to share more of their talents, skills and energy with less experienced salespeople.