Once per year promotions seems rough. If it is denied for some reason you can’t try again in 1-2 quarters. Although maybe that is a good way to prevent people from creating promotion oriented systems (ask POS).
That seems to have been the standard for every job I've ever had, across disciplines and sectors. I assume this is not the norm in silicon valley?
What is more interesting is if there is a way to align promotions with stuff that's good for the company. The issue isn't that people want to get promoted, it's that they get promoted to do things that are negative for the company!