I suppose that's something you could call it, but it's a little misleading because this so-called "input lag" is a result of the monitor not being able to paint all pixels from the screen buffer to the screen within short period of time (ideally, this should be 16.6ms for 60Hz). This means that system events such as mouse movements (etc) are not drawn/re-drawn quickly enough, which leaves a noticeable disconnect from the whole desktop paradigm. It's so slow that users often (too often) overshoot the intended target and click in the wrong places.

It's also misleading for the monitor to report 2560x1440 at 60hz when there's a 100ms response time. Even at 1920x1080 the monitor is sluggish. We bought these monitors knowing that in 4xFHD mode (3840x2160) the refresh rate would only be 30Hz. We thought this wouldn't pose a problem as they would still make decent 2K monitors. Alas, this is not the case. They don't even make good FHD monitors.

There's no point wasting anyone's time here. I have vented my frustrations, and we (the company) will be returning these monitors as not a single employee wants to use them.

The baseline has been 60Hz for many years now (and a minimum 5ms response time). Why you guys decided to try your luck with 30Hz and a 100ms response time leaves me gob smacked. Your users deserve much better than this.

That is all.