There are two sets of developmental needs for any employee. One set is behavioral, where they may need to undergo training in teamwork, interpersonal behavior, cross-functional awareness, stress management, etc. The other set is skill development training. This will be decided based on any identified deficiency in their present job and preparing them for future responsibilities in case the management has worked out their career planning.
Training needs should not be unilaterally decided by the boss, but they should be discussed with the concerned employee, and a consensus training needs package should be arrived at.
Having worked in a large corporation, I know that this activity is often taken as a ritual ("KHANA PURTI"), and enough interest is not taken in arriving at the training needs. In some cases, the training package is decided first ("SQUARE HOLE"), and then candidates ("ROUND PEGS") are frantically searched to attend the program. In such cases, money is wasted.