Firstly in the UK the very worst can be temporarily closed for a short period and the public would not know. They can be told to take emergency measures and reopen following a re inspection say in 7 days. The rating would then be given following re inspection and presumably after forced improvements. Also people receiving low ratings can request re inspection.

There is of course the more important issue for some and that is what is personally acceptable. Set low enough standards and you will always be content. Your comment implies this is your position. Fair enough. Food hygiene standards in kitchens I don't see bothers many, me included. The issue of low ratings is also an indicator of whether you can trust and have confidence in the people that prepare food for you. Again, not for you. Fair enough again. I presume I can trust people that prepare my food until there is contrary evidence. Hygiene ratings are such evidence.

With respect to your second point, you also do not seem to understand all of the elements of inspection.

I do not keep staff training records or records of toilet cleaning or supplier date records and food rotation records. This would cause me to fail a commercial inspection. I do however have procedures and processes and a degree of kitchen cleanliness that would pass that part of an inspection. Our kitchen for example has a weekly "deep clean".