Not all tests are unit tests. I had a property test I was running that I eventually just turned off because it was working just fine on everyone's machine but would fail 60% of the time on Travis due to time out issues. It got worse from 30% after Travis was sold, I suspect they are skimping on the aws. I probably should have written a more effect dependent timeout, but it was hard to justify recoding something when your test is long and your retrigger is via Travis.