I have also just had 1st cancellation by phone. I'd only cleaned her twice, once trad and the 2nd time wfp. I lost 2 others as well last week. 1 didn't like wfp and wanted me to do it trad again. I told them if it was a quality issue i would always put it right but if not then sorry.
Another complained that a window sill upstairs wasn't clean. She had been a good customer from when i'd started 2 years before but last month she complained about a window sill downstairs. I always clean the frames and sill but she probably had a point upstairs with wfp, as i couldn't see.
There was another issue the month before as well.
Oh yeah, new door fitted which had i glass pane instead of 2. She asked if her £3 job (front only) was still £3 because there is less glass now.
Dropped.
All my customers know i guarantee my work so it isn't about the finish but the method.
There are about 5 more who i anticipate not liking wfp, but i haven't heard anything yet.
The 2nd month will reveal all.
Do what's best for you.
As long as you treat your customers with respect your supply of them should never dry up.