I have never cleaned a "loo"........women do it....the wife, OH or woman that cleans.
BUT..I always...always use a brush after using the toilet AND put the seat and cover down.
Once a week or so, I pour some caustic soda down the loo, add a kettle of hot water, and retire behind the shower curtain......the bog comes up lovely !
I always assumed they were just for removing skid marks before someone else saw them. Clean with flushable wipes, followed by toilet cleaner fluid around the bowl, and finally drop a deep clean tablet in. Seems to work.