I remember paying a neighbourly acquaintance (professional decorator/builder type) to line all the walls in my house about 6-7 years ago. He said it would take him and mate X days.
I turned up at 9am the first morning and they were sat in the van having not even started … eventually they came in, did some work inbetween a few breaks, then scarpered at 3pm.
I saw them the next morning and said “You’re not counting that as a full day are you?” “Yes,” he says. “What, about 4 hours work? Sorry, but I’m paying you to work full days, not half days. Therefore I’ll pay you half for yesterday and would appreciate it if you work full days from now on.”
Both of them then worked something like 8am-4:30pm and TBH did a brilliant job. I felt awkward having to confront the ‘boss bloke’ seeing as him and his wife were good friends of my then gf. But at the end of the day I expect the job done properly. End of.