Do some lasers result in full shedding of treated hair while others have only partial shed?

I had a number of sessions two years ago with a clinic that went very well. To the best of my recollection they used an Alexandrite laser. I'm a male looking for thinning of chest hair and after each session all hair shed and I was very happy with results. I moved in the meantime and went to a new local clinic 3 weeks ago. They used a Soprano Ice. I've only had two small patches of hair shed. Most hair seems untreated. They told me this is normal for this laser, is this true?