Employees are promoted based on merit and performance. They make a business case for the promotion and then are assessed according to their overall performance and feedback from seniors and peers.
Promotion opportunities for juniors went from automatic to merit based, which is a corporate way of saying it went from being based on your raw experience and tenure, which rewards loyalty without fear, to being based on the biased opinions of seniors, leaving your financial and career future being up to whether or not your personality clashes with your superiors or not.
For the first five years from grad to manager, yearly promotion is expected if you are generally capable. This is after yearly performance reviews.
The promotion cycles are infrequent, the progression also seems regimented (neither a good nor a bad thing necessarily).