If there are diminishing returns to capital, then increases in the capital stock

Over the past year, three of the star salesmen at family resorts international's corporate office have been lured away to competitors. on top of that, karina, the general manager of the sales department, has noticed that most employees come in, do their jobs, and leave. family resorts offers a good salary, benefits, and tuition reimbursement, as well as a number of development and training programs. most employees seem contented enough, but karina would like to do something to increase the level of engagement among her staff. what do you think karina should do?