I don’t agree that every massage sessions should hurt like hell. As a massage therapist myself (as well as a strength coach, etc…), I don’t take pride in making my clients squirm with pain every time I work on them.
As a given rule, if a tissue is relatively unhealthy (i.e. ischemic, fibrotic, etc…), it won’t take much pressure to elicit some discomfort. Conversely, healthy tissue should be able to take around 5-10 pounds of pressure with only mild discomfort or a feeling of “pressure” instead of pain.
The goal with soft-tissue work is to use the “right” amount of pressure for the area being worked on; kind of a Goldilocks “just right” approach. Also, there is no substitute for precision and specificity with massage release techniques. If you know where you are at, you don’t need a ton of pressure. The client however, may percieive that a lot of pressure is being used when in fact, very light pressure is being applied.