Lotus Notes as a thick client application was a dead end but the Domino server could have lived on as a back end database for web applications, if IBM had any vision. The core technology of a fast, secure NoSQL document database with multi-master replication actually worked really well (at least after they fixed the index corruption race condition bug that I found). But it had a weird stupid limit of (I think) 64GB per file with no automatic sharding support. And they never added XML or JSON as native data types. So it gradually became useless. What a shame.