I have been seeing current T almost weekly for about a year. There have been several sessions (6 ish?) where I felt they were wasted. Some of these wasted sessions were due to me being closed up, some due to my T being off, and some due to a mixture of both. It's always frustrating when it happens, but it is what it is. I figure nothing in life goes smoothly every single time. We all have our off days, too. It doesn't happen enough to where it's a concern -- it's not a regular occurrence. If it happened maybe as little as once a month I'd think that would be a serious concern for me and I'd probably look at finding a new T.