Sharpness
It is almost never the lens at fault
When you have a blurry or fuzzy picture, it is so easy to blame the lens. After all many reviews compare the sharpness of lenses all the time. Speaking from experience, it is very rarely the lens at fault.
If you know what the problem is, it is easy to correct
More modern cameras can automatically correct the known distortions for lenses at different focal lengths. Here I use the Nikon 28-200 which at 28mm has very visible distortion. I take two separate pictures, one without any correction the other with Auto distortion control set to on on a Nikon D610.
These pages are for Amateur Photographers and not really for seasoned photographers and professionals. I have no affiliation or commercial interest with any brand/make. I write from my own experience. I ended up using mainly Nikon, so I am more familiar with this brand than others. See price for notes on pricing as well as photography related links.