I struggle to understand the hotel 4-star rating, ...

I struggle to understand the hotel 4-star rating, it is a good 3-star for the main building and a bad 3-star for the annex. While it has indeed been refurbished, rooms in the annex are pocket-size and bathroom closet-like. I could hear my neighbor's different businesses in the bathroom. Internet connections are awfully slow and censoring. No mini-bar/fridge. No water bottles in room. While the breakfast buffet seems abundant, a closer look (e.g. the very limited choice of breads, the absence of a decent expresso machine) makes it fail passing anywhere above the 3-star bar. The conference center is decent, again not 4-star. No power plug on tables (forget non-UK plugs). Overall, not bad, far away, but do not expect a 4-star experience. Only the grounds are shining: the very nice garden and proximity of the Thames. A 3-star disguised as a 4-star...hence my disappointment and low rating.