I often try to look critically at what I offer and I even sleep in guest rooms and use all the facilities which I offer to see if there is something which needs improving.
Also, when I stay in a local guesthouse, hotel or b and b I sometimes ask for the manager and just tell him or her of any problems which I encountered. I find it is the the gentlemanly thing to do = tell the owner first if there are any problems and do not cause any unnecessary harm to a business.
It may be a peculiarity of the area where I live but I found that owners often take my PRIVATE criticism badly. Don't they realise that whatever I say even if it had to be unfair is PRIVATE?
This is one reason why often ask my guests what they would do, if they were me, to improve the property. I did get some useful suggestions but also some impractical ones. But I always show my appreciation for the time that they spent telling me about what they liked or disliked