A sheet signed on Friday says that somebody remembers a visit happening. It does not say when the carer arrived, how long they stayed, or what they did. When a family complains that nobody came on Tuesday, a signature is the start of an argument, not the end of one.
Commissioners know this, which is why so many contracts now ask for visit data rather than sheets. Inspectors know it too. What they want is evidence that was created during the visit.