I usually offer 0,6-0,8 of the salary they will get at middle level (i.e. reaching full autonomy and being able to complete 90% of tasks). This offer is limited

I usually offer 0,6-0,8 of the salary they will get at middle level (i.e. reaching full autonomy and being able to complete 90% of tasks). This offer is limited in time: they have 6-12 months to grow or they are out. Recognition of their personal growth and higher salary is a good motivation to stay if there’s no red flags in the company (poor processes, toxic environment, frequent overtime etc).