Preview's more than just a PDF viewer. It's fast (opens almost instantly, low or no UI lag under almost all circumstances), light, renders PDFs excellently and

Preview's more than just a PDF viewer. It's fast (opens almost instantly, low or no UI lag under almost all circumstances), light, renders PDFs excellently and without the artifacting and lag that's common in other readers. Adding signatures in it's a breeze. You can easily, visually, assemble new PDFs from pages of others. I'm not afraid of using features because they feel fragile or slow things down. It also has all the image & photo editing features I need 99% of the time. Similar for Pages and Numbers vs. Libreoffice or Google Docs. They're faster, lighter, and (despite having spent more time using Libreoffice/Openoffice total in my life) easier to use effectively. Another case where I don't hesitate to open them because they're quick to open, don't hesitate to close them for the same reason, and can forget they're open in the background because they're so light and don't bloat or crash when left running. Notes versus Google Keep or whatever is similar—it's a real program that opens very fast and is respectful of resources when running, not some browserware junk. KDE seems to be the most-integrated Linux UI but I've never managed to "click" with it despite trying since 2 (maybe something in the 1 series, actually? It's been a long time). I don't like the K-suite programs—they seem really heavy to me, and always have—and all the integration stuff goes out the window if you use others, plus then you're usually mixing GTK and QT which is rarely super pleasant. The "just works" integration of the K-suite has also never really "just worked" for me—bugs and inconsistency galore.