My first dev job was a Notes developer. It really was an amazing piece of tech in hindsight. IMO their real folly was chasing the web trend; at its heart it was a groupware product, and they tried to make it be too many things to everybody. I spent most of my time trying to wrestle it into doing things it wasn't meant to do. It got me extremely proficient with LotusScript which led to other opportunities (Hello ASP!) but the whole thing is a shame. Had they stayed in their lane with the product, it might still be alive and widely used today.
For that matter, had they invested in a web plugin that treated domino as a thin client server, they may also still be around today. Though load balancing would probably take a bit more work.
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