A pitch deck shouldn't be a boring business presentation. It's a narrative that tells your company's story. Depending on your stage and your particular journey, this ‘story' can take different angles: solving a pressing problem, a unique business model, remarkable traction, revolutionary tech...
If asked to recall the tune from memory later on, I could whistle it though not necessarily beginning with the pitch I had heard it start from — in other words, the tune would be correct, but not necessarily the key. But I would have been unable — or at least not without a lot ...