Appropriate design?, name?, payment methods..?.. just strong in the UK?
I think that the UK consumer wants to deposit monies with a reputable company and a brand that they can trust.
Firms such as Ladbrokes, William Hill, Corals and to a lesser extent totesport and Betfred have had a high street presence in the UK for 40 years, so your average British consumer will have some kind of affinity with these brands.
Add to this the bet365’s, Betfair’s and Skybet’s who have considerable above and below the line presence in channels readily available to the UK customer have also raised brand awareness.
I’ve worked for companies from an entry to market level as well as those with a terrific UK brand (practically an institution!) and there’s a phenomenal difference in acquisition rates amongst UK traffic.