For Room Correction DSP/Software- How often do you use it?

I've used room analysis tools (calibrated microphone and REW) and adjusted PEQ in Roon. This can be very useful in doing what I did set your own filters as well as analysis of room if you want to use traditional style room treatments and speaker,  listening position placement. Full use programs like DIRAC and ARC are easier but I've never been a huge fan of either. I've gotten better results using REW. 

With that said the one quick use full program that in my opinion and use case  outperforms Dirac or ARC  by far and REW is GLM but it is proprietary to Genelec smart monitors. As for getting an excellent FR with minimal room treatments and incorporating subwoofers I've used nothing to beat GLM it is that good.

So what changes in your room that you need to use it very often?

For those that own such devices how frequently do you actually use it and what drives the need for its use? 

Um, every day?? I mean, I have configured it once, but I listen to it whenever my stereo is on.  I wrote about it extensively here:

What is achieved from its use that is outside of more traditional approaches such as speaker placement, room treatment and/or component matching?

It’s a tool. In most rooms, a balance of room treatment and EQ, especially in the bass regions can really improve transparency.  When you can't control placement or room treatments EQ is the only option you have left.

Okay.