Number of clicks
If you have worked before, then remember how managers estimated the design in clicks. The fewer clicks the user makes the better. Arguments like «well, this is an extra click» were discussed absolutely seriously (immediately after the proposal to place everything on the first screen).
In fact, it was not because of stupidity, but because of the slow Internet. Users tried not to make unnecessary clicks, fearing a long and expensive download.
Now the Internet has become fast and cheap, but people still don’t want to delve into loaded pages. Don’t be afraid to shorten and hide all nonessentials behind links.