Back when I had very slow DSL (as opposed to just slow DSL) I found it was almost impossible to install complex container layouts because the Docker client was not at all smart about caching and failed downloads.

Later on I worked at a place that had gigabit Ethernet and got into an argument with the CTO who couldn't believe the build process (which built software packed it into containers and ran a system based on containers) took 20 minutes. I set my stopwatch and it was 18 minutes and 27 seconds and a lot of that time was Docker doing ultimately meaningless I/O.

People think Docker is doing something positive for them when it is really killing their productivity, making their projects late, giving them time to go get coffee, etc.