Also, in my experience, writing UI code is usually more(!) work than writing the functionality underneath, because
a) styling / layouting has to be learnt from scratch (e.g. because of a proprietary language, e.g. QML or QWidgets for Qt)
b) you have to take care of every frikkin' single user interaction (which becomes worse the more dynamic and custom your UI is), and building proper accessibility is also no walk in the park
Also, in my experience, writing UI code is usually more(!) work than writing the functionality underneath, because
a) styling / layouting has to be learnt from scratch (e.g. because of a proprietary language, e.g. QML or QWidgets for Qt)
b) you have to take care of every frikkin' single user interaction (which becomes worse the more dynamic and custom your UI is), and building proper accessibility is also no walk in the park