I believe a fundamental principle of making and keeping business happy is to keep short accounts. Keeping short accounts is: not allowing yourself to get into debt, it's saying sorry when you're wrong and doing your best to avoid making enemies. It's bothering to go the extra mile for no discernible benefit, it's being polite to strangers, it's doing the right thing when no one is watching.
It's being respectful to all people and keeping on good terms with your bank. It's promising and delivering. It's sorting things quickly, and without unnecessary fuss. It's being a good businessman and being a good customer.
Short accounts are paid up quickly, they are polite exchanges between people, they are never taking anything for granted. It's not just customer service, it's supplier service, it's other road users service, it's coffee seller service. All those you deal with should be treated as you would treat your best customer.
It's because there are very few people who don't deserve to be treated with a lot of respect.
It's because one day you might become their supplier or they become your next contact.
It's because their best friend may turn out to be someone you've always wanted to know.
It's because when you're the one doing favours for people, you're in a great position to call some in if your world comes crashing down.
It's because it's an opportunity to be different, to surprise and delight.
It's because you never know.