Well look at Leeds. It's putting up a new skyscraper on a yearly basis and has a new york-esque skyline. However, most cities in the UK don't do it because the metropolitan population is too low, the UK is centralised so most big business is in the city of london, where corporations who can afford to build skyscrapers tend to build them.
Also, councils may sometimes have to put money towards them and only London, Leeds, Manchester, Birmingham, Liverpool and Glasgow can afford to do that.
Also companies have to look at how attractive a city is and how much money it can make in a place over the years. It looks that over the next 20 years there will be growth of skyscrapers in London, Leeds, Liverpool, Newcastle because they are the most economically viable cities for the future.
Also because some cities are small in the UK (most are actually), a company wouldn't waste money on building a skyscraper somewhere like stoke when they could just build a cheap warehouse outside the urban area with cheaper land prices and make the same money, if not more (depending on where it is in relation to maybe a motorway).