whenever you need these three things together: decentralization, secure, and auditable data. Could be the cases when we do not want to give the authority of the data to a central resource. Like, what if all educational institutions host blockchain nodes to store educational records of their students. There can be similar use-cases but most of the noise is due to a buzz word and companies want to cash it.
What if there is no more blockchain technology tomorrow morning, will your project survive? If your answer is YES then you might need to rethink about it.