I get great reviews, positive comments on cleanliness, breakfast, communication, making people feel welcome and so on. I work extremely hard to be a good host. Yet I have 4.8% 5 star rating.
The majority of my 4 stars are for 'overall experience'. This could be because the sun did not shine that weekend, they were disappointed with the museums, perhaps they were not keen on the supermarket nearby, maybe they wished Cambridge were Ibiza ..or in an ideal world their room would have had an en-suite bathroom.. who knows?
'Overall Experience' is unquantifiable. Neither the guest nor the host know exactly what it is. If a guest gives 5 stars for everything else except 'overall experience' what is the host supposed to do to improve? Move house?