LET ME BE YOUR MOTIVATION

As the Managing Partner and Principal conductor of your law firm orchestra how do you get your people to release their forces to make it happen? This is the substance of the problem of motivation.
Over at Microsoft, they have solved the problem of how to motivate despite the reality that everyone in their industry already has a great salary and can get a decent job anywhere else thus making the money lever ineffective.
They offer them the opportunity to do great, creative work and then recognition by having the work used. And they only hire people who live on doing great work and this is the business culture they have.

Lawyers are a different breed and the economics of legal services suggests different levers, namely: Offer independence and you will attract the best of the best.

The rest is this. You do not want to serve as a mere training ground but the reality is that it is a fundamental law of labour that you cannot force an unwilling employee on an unwilling master.
To have solid people you must accept the fact that some of these people will leave. This is the reality at every company with a solid rep so the question for your law firm is would you rather have a team of stars with the reality that some of them will definitely leave taking away the investments you have made in them or a team of helpers to execute the ideas of the one master.
The option of golden anchors or handcuffs exists for you as well and has been quite successful but according to Drucker the chaps who give in to the anchors tend to become resentful because they feel they have been bribed and were unable to resist the bribe.
All of this affects the team spirit and the attitude with which your people go about their work and it matters because when the Chips are down or a superhuman effort is required to make it happen, every team member goes 'why should I bust my chops for these people?'

A word on the motivational training business: you need fundamental, actionable intelligence NOT songs, dances e.t.c.
The following levers:
1. Overwork inspired well paid people
2. Hire 5 right people, work them like 10 and pay them like 8
3. Company loyalty must be legit because it has almost no credibility so you will have to work really hard on that one

Please note that it is unlikely that you can motivate underpaid people. You must offer an adequate wage unless you are relying on the adage 'the hunger of the labourer will drive him' as a firm policy.
Where you are going is when your people get the choice to jump shop they have valid reasons to remain at your shop.
This means clarity of what you expect from them and what you offer them: no tricks.