It has just come to me in a flash!
There are hundreds of pensioners and people who've paid their mortgages sitting out there getting no interest on their savings. There are hundreds of self-employed people with perfect mortgage payment history unable to get a loan.
I was aghast as always yesterday when I read the line on my mortgage statement that the £12000 I paid last year had brought my mortgage down £2900...
How do you go about setting up a bank where pensioners lend to self-employed people who prove they are unlikely to default?