Today in Britain there are over 2500 breweries, most of whom brew an ever-changing range of different beers. On the bar of any decent pub, or shelves of a good bottle shop or supermarket beer aisle, the choice can be overwhelming. People make snap decisions so quickly we don't even notice.
And the design of a beer label, pump clip, bottle or can has to do a lot of work to stand out, get noticed, and suggest to the thirsty punter that here is a beer they will enjoy.