So what is the recommended interval between cuts? That depends.
Chin length and shorter: 10-12 weeks.
Chin to collarbone lengths: 3-4 months.
Collar bone to armpit lengths: 4-6 months.
Below armpit length: 6 months or more.
Keep in mind a haircut absolutely needs to be shaped in a manner to support growth. With that accomplished, those intervals are all very achievable. In certain shorter instances a client will likely need to learn to manage subtle styling changes as it grows, but having a good cut to begin with makes this a much easier task. I actively encourage clients to appreciate the process of growing out a haircut and to book in when the shape fully has stopped cooperating. This is entirely possible with work that has been cut well.
A great haircut is similar to fine dining and massage experiences. Attempting to enjoy these things too often leads to decreased satisfaction in short order. As hairdressing is a personal service, it must be conducted in a manner that promotes a positive professional relationship. A haircut that grows out well enables the client to appreciate it for a longer period of time, enabling future experiences to be similarly rewarding each and every time.