I worked for a company that grew considerably for 10 years and then lost its biggest client and folded quickly. We had spent a few years reworking our platform in a way that might have been successful enough to weather the storm of losing that client, but technical debt really slowed us down.
Technical debt may not have killed the company directly, but we have to wonder how we might have done if we could have spent more of our time on new development.
This is revenue diversification not technical debt. Companies with a single customer funding the business should be actively pursuing a high priority strategy to reduce this risk.
You misunderstand - our software itself was full of technical debt. We spent a lot of time dealing with the consequences of that debt, and I'm wondering if we'd have been able to hit vital targets sooner without it and possibly have survived.
Technical debt may not have killed the company directly, but we have to wonder how we might have done if we could have spent more of our time on new development.