If you used big Data tech (Hadoop/yarn/spark) when you didn't actually have big Data (PB), it was slower than columnar databases so the shine wore off.
This. The falling cost of storage and increasing speed of SSDs means that for most use cases a column store database is significantly faster and cheaper.
Yeah. Companies don't like it when their expensive fancy new Hive/Hadoop cluster takes longer to run an even moderately complex query that's core to their business than their existing Oracle or SQL Server DB.
For some reason there's ridiculous levels of FOMO in executive ranks, so any new trend is something they need to jump on like it will be what keeps their company around in 10 years. The result of this is fad-jumping, which I've seen happen from Big Data to ML to Blockchain, costing companies millions that could have been better invested in their own products or offerings and actually competing better. It's a really expensive educational cost for leadership IMO.
