First, the width of the app window is fixed and cannot be resized. And some wide columns are fixed in place too, meaning that I can only see three columns at the time (out of 30) and therefore I am constantly scrolling left and right. On top of that, every time the window loses focus it does a weird 2-3 seconds refresh when you come back. As a result, we all write everything in Notepad first and only open SAP when we know we won't need to click away anymore.
Every single cell in that "spreadsheet" can do at least 50 things, but I have never managed to get them to do what I need. If I need the specific code of my position I copy-paste it from last month because that cell's search function has never returned anything useful. But if I check last month's data I lose the data of this month that I didn't save (plus the weird refresh thing happens here too). And if I save something it's there forever and cannot be edited. As a result, if I don't have my employee and workplace codes at hand at the beginning it's faster to throw the partial data away and start all over.
Some fields auto-complete, but I'm not sure under which circumstances. A colleague found that double clicking in a specific cell triggers this, but none of us knows why this specific cell.
This is a single app I use exactly once a month. Imagine having to use something like this every day. Even worse, imagine testing this app and saying "yes, this expensive, slow, uncomfortable app is exactly what my company needs, and I'm glad to know that you expect me to adapt to it instead of the other way around".