Good, QGIS is one of the projects that can be put closer to the bottom of the stack in that XKCD comic. I've seen QGIS being used just as a visualisation tool, and i mean it's good at it too, but even in a limited use case i am aware of it was used to do important infrastructure work like planning water pipelines and predicting failures for said pipelines.

Edit: https://xkcd.com/2347/