I'm not testing those stupid views!
Over the course of a Rails project, views that started out very simple can evolve into a complex mix of HTML with complicated nested Ruby conditionals. They become hard to understand, hard to read and hard to work with. Fixing an edge case in those views may involve the painstaking process of writing of an end-to-end test to ensure the bug has been squashed. Those kind of tests have quite an impact on the overall runtime of the test suite, so typically you don’t want to write too many of them. Especially not for edge cases. The more end-to-end tests you have, the harder it becomes to make changes to your views because the tests have all kinds of expectations of them.