Charles Jennings promotes a 70:20:10 framework for organizational learning, where on-the-job experiential/informal learning and social learning represent the preponderance of each employee’s overall learning. Only 10% is from formal learning activities.
The reason this framework works is that it more or less reflects what’s actually true for employees in the typical workplace. Formal education has its place in preparing people for the workplace. Once those people become employees, they have a job to get done. People aren’t hired to learn, they’re hired to increase productivity or capability. There are productivity expectations and organizational needs to be met.