In March our biggest customer left. They were 31% of our revenue.
I'd known that number for a year. I told myself it was fine.
It wasn't, and the reason wasn't them. Every other customer took six weeks to get live, so we never had the pipeline to make one account matter less.
So we spent the next quarter on one thing: getting a new customer live in a week instead of six.
We cut the setup call. We scripted the imports we had been doing by hand. We stopped customising the first dashboard for every account.
None of it was clever. It was work we kept putting off while one account paid the bills.
We signed 14 customers that quarter. Today no customer is more than 12% of revenue.
Being liked by one account isn't a business. Being easy to start with is. It took losing the account to see the difference.
If one customer leaving would hurt you this much, start with how long it takes the next one to go live. That number tells you more than your biggest logo does.