It creates a lot of unnecessary tension between management and employees if employees can't just assume that they'll be rewarded for outstanding results and don't have to ask for it. If there's a tacit agreement that if you do great work you'll get a raise with a quarterly or semi-annual review process, employees don't have to get distracted by thinking about when they should ask for a raise or whether they need to get a competing offer to get leverage to ask for a higher raise.
Management might have better things to do, but if this creates an atmosphere where employees feel under-appreciated, they'll leave, and this churn can really hurt the company, which makes it a huge problem for management that could have been avoided by rewarding high performing employees earlier.
I agree that there is a cultural bias in favor of this type of wage structure, and that any company that ignores it does so at their own risk, as it will create unnecessary tension, as you say.
But still I bristle at tacit assumption behind the OP's point that both the amount and timing of my wage increases should rest in the hand of a manager. The OP is saying that managers should be enlightened about it, and I'm saying you can't trust management to be enlightened about it and should take charge of your own compensation.
Management might have better things to do, but if this creates an atmosphere where employees feel under-appreciated, they'll leave, and this churn can really hurt the company, which makes it a huge problem for management that could have been avoided by rewarding high performing employees earlier.