I would add in addition to being more predictable it's significantly easier to test. If you fully embrace having stateless components, those components take inp

I would add in addition to being more predictable it's significantly easier to test. If you fully embrace having stateless components, those components take inputs(props) and have a straightforward output (the elements they generate) which shouldn't have any side effects. A unit test can easily capture this behavior rather than building up a large test suite to test a button click.