To add English (United Kingdom) as a language feature for keyboard language. Because not everybody spells the way Americans do
Just to change the options for language settings to better suit people living in other countries.
Derek Williams commented
Since the UK is the country where English originated, it's a tad demeaning to have Microsoft USA telling us off for 'misspellings' *in our own language* for words like 'colour,' 'neighbour' and 'aluminium'.