Even though you are passive during a massage, the muscles are being stimulated in a way that is similar to a workout; cycling through a repeating pattern of stretch-contract. This creates micro tears in the muscle, increases blood flow and eventually results in inflammation. The inflammation is what causes the soreness and is also what promotes healing. So, yes it is completely normal to feel some soreness following a massage.
Just as soreness lessens as you become more efficient with a specific exercise, soreness also decreases with repeated massage; the body builds a tolerance to the level of intensity. Increase the intensity, and the sensation will follow suit.
This does NOT mean “no pain, no gain”. While there is a certain level of soreness that is therapeutic, not all post massage pain is good. There are situations where there is already an ample supply of inflammation around an injured area and aggressive massage can slow down or even reverse the body’s natural healing.
The harder your knots are, the more time we need to knead them out. It’s a bit like buttering fresh bread… You cannot spread cold, hard butter over the bread in a hurry without destroying the bread. You have to let the butter warm up and soften in order to get a good result. A little skill and patience can go a long way!
A recent tightness may be well addressed in 60 minutes, where an old pain may take several consecutive visits (and some home exercises) to see results.