Most Indian SMBs earn a large share of revenue from a small number of accounts. Those accounts are usually handled by the founder, a senior manager or whoever won them, alongside everything else that person does. Nothing looks wrong until a buyer changes job, a competitor quotes lower, or a quarter passes without anyone asking what else the account needs. The relationship is real. The method behind it is not written down anywhere.
Why it persists. Existing customers rarely shout. New enquiries do, so attention goes to whoever is loudest this week. Account management also looks like a job for a large company with account managers on the payroll, and hiring one before the revenue justifies it feels risky. So the work stays informal: a call when something is needed, a visit when there is a complaint, and a plan that lives in one person's head.
If it stays unresolved. Concentration turns into exposure. A buyer moves, a competitor calls at the right moment, and a large part of your revenue leaves in a single quarter. Meanwhile the orders you could have won inside those accounts, a second location, an adjacent product, a service contract, quietly go to whoever asked first.