I don't travel all that much, but do go away on business a couple of times a year and we often have a couple of stays away in a hotel each year. Over the years, I've ended up visiting a whole range of hotels of various ratings and price ranges.
And one thing that's become abundantly clear is that there's at best a tenuous relationship between the quality of the hotel, the price you pay, and its mysterious star rating.
Looking at quality against price, it's certainly not the case in general that better quality costs more. While within a certain locality, that may be true, but across the board I tend to see the opposite trend: increased competition tends to simultaneously drive down prices and increase quality.
And what of this star rating? In my experience that tends to correlate with size. Larger hotels offer more services, and that tends to be reflected in the rating. But it's just a measure of quantity, not of quality.
I've stayed in large hotels that feel welcoming and comforting, and those that are cold and mechanical. The same is true of smaller establishments (although recently we've tended to stay in more up-market boutique hotels that have tended to give vastly superior levels of service).
The star rating of itself is almost never a guide to how good a stay you're going to have. If anything, looking at the star rating is harmful, as it prejudices your expectations, which may be why I've been underwhelmed when I've stayed at four or five star (so-called luxury) hotels.