A succinct way I’ve framed the split is that a front-of-the-front-end developer determines the look and feel of a button, while a back-of-the-front-end developer determines what happens when that button is clicked.
Doing it right requires a different pace of working and a much broader thought process than “ok, let’s get this thing out the door.” Which is super tough because most workplaces place a huge emphasis on getting things out the door, and fast. Little agile tickets that are expected to be completed in micro sprints to me seem to be antithetical to doing it right.
In Broussa in Asia Minor, at the Green Mosque, you enter by a little doorway of normal human height; a quite small vestibule produces in you the necessary change of scale so that you may appreciate, as against the dimensions of the street and the spot you come from, the dimensions with which is is intended to impress you. Then you can feel the noble size of the mosque and your eyes can take its measure. You are in a great white marble space filled with light. Beyond you can see a second similar space of the same dimensions, but in half-light and raised on several steps (repetition in a minor key); on each side still a smaller space in subdued light; turning round, you have two very small spaces in shade.
From full light to shade, a rhythm. Tiny doors and enormous bays. You are captured, you have lost the sense of the common scale. You are enthralled by a sensorial rhythm (light and volume) and by an able use of scale and measure, into a world of its own which tells you what it set out to tell you.