The best motivation arises within. Certain players have IT, Anson Dorrance's "competitive fury." Players are not cosmic vending machines that we feed magical coaching coins.
As first year medical students, we learned about compliance, getting patients to adopt lifestyle and medication recommendations. But teachers emphasized noncompliance factors - barriers, efficacy, severity, and susceptibility.
What barriers demotivate players? Paul Robinson writes in Foundations of Sports Coaching that two demotivational factors are queues (lines) and "drilling for drilling's sake." We tell players to "play with purpose" and we must "coach with purpose." Practices should emphasize technique (skill) and tactics (strategy), conditioning, and the mental game. Examine whether our practices achieve that and ideally combine elements (see Lagniappe).
Is practice working (efficacy)? The Turkish proverb advises, "measure a thousand times, but cut only once." If practice is working, then we should have specific, measurable progress from both practice and competition.
If we score "3 by 3 shooting" (half-court) or "3 by 3 by 3" full court over 3 minutes, we should see gains over time.
If a player's offseason workout includes "Pitino 168", then she should score higher over time.
How severe is the compliance issue? The ultimate individual consequence is fewer minutes. I divide each half into five, (roughly) three minute segments. That provides fifty three plus minute slots per game. With twelve players, two players get five rotations and ten get four. Everyone gets developmental time and two players earn extra minutes. Rotation brevity demands high effort.
Are you susceptible to 'consequences'? In a developmental program, aside from parental cost, no player should bear performance costs. Playing struggles don't get punished. What's the benefit of telling twelve year-olds, "you're not good enough?"
Be authentic...but realistic. Dispense praise to praiseworthy actions, but remember to praise effort. Maybe Dean Smith could praise "execution not effort," but that's untrue for youngsters.
Add value. When we're doing our job, success leaves footprints. The team improves and players acknowledge both improvement and feeling valued. Results increase motivation more than motivation produces results.
Define the process, the costs and the benefits. Get the "buy in." I often forward the tentative practice schedule to parents to share with players. They see the emphasis on fundamentals first, offensive development, team defense, and execution of special situations. They don't have to agree with it, but recognize there's a process to improve their child and the team. Disorganization would demotivate me as a parent.
Lagniappe: drills should translate to game play.
We run through individual elements, with defense and then have players play. They gradually learn offensive and defensive execution and decision-making. I am fortunate to have a very capable assistant so we can run two productive groups at once.