We like to use the term, "checkpointing," in career development. These are informal positions that team members earn through overachievement that don't cost your organization anything other than investment in your people.
When applied correctly, these informal positions add efficiency and production to your team while your people develop new skills, gain exposure, and explore their career opportunities.
A few ideas...
When possible, put checkpoint place holders in your career development plans. This allows for flexibility as you match individual interest to your needs, but it also sets expectations via a social contract. This will help motivate your people to the next step at their own pace without creating the risk of promising advancement opportunities when there are none.
It's important that your team understands these are extracurricular privileges. They're still responsible for their core responsibilities and production. Just like sports in high school, if their grades slip, they can't play in the big game!
New York Times bestseller, Daniel Pink, teaches us that compensation comes in multiple formats: mastery, autonomy, purpose, and pay.
Everyone needs their own unique mix to feel satisfied, so you'll need to tap into them in different ways to find the perfect mix as you apply them to the concept of checkpointing. It's also a delicate balance. If you give too much, someone might stop innovating out of the fear of losing this additional compensation. Conversely, not enough and they'll be focused on being under compensated instead of the task at hand.
Most early career professionals don't place significant value in skill development unless it's directly related to their ideal path so identify it and feed into it. If they want to be a Chief Revenue Officer someday, get them exposure to those functions as they succeed.
If you can give days, half-days, or hours off, do it. You'd be surprised by the value that some get from cutting out of work early on a Friday, coming in late on Monday morning, or just not being hassled for taking a long lunch. You have to pay them the same amount no matter what you do, but the key is to find ways to give them more flexibility on their own terms.
Just make sure that they understand that they're still being held to the same accountability standards.
Particularly for those that are interested in a management track, giving them a "Team Lead" title with additional responsibilities can scratch an itch related to helping others and contributing to the team/function/business in a unique way. As they add value, it's critical that they feel that their contributions are having an impact. Demonstrate it through public praise and business metrics.
All of that being said, when someone is highly money-motivated, don't be afraid to incentivize them with accelerated compensation structures, bonuses, or non-monetary payments (free lunch, paid subscriptions, etc.). Generally, the trick here is to position the compensation as more valuable rather than the amount itself.