Theming in Drupal8 was a massive shift from phptemplate to twig, but its more than changing the syntax. We changed the way of thinking about Drupal theming. Drupal twig theming is easy to learn, powerful, flexible and overall as awesome as warm coffee on a rainy day. The downside is that all the things you learned in Drupal now have to be relearned - Yes it's by design.
Over the last 4 years we (the frontend drupaltwig group) we got one burning question from the Drupal community.
“How I do this right the first time ? ”