Nobody's perfect. No company is perfect. As consumers, we hope that companies will produce products that properly function and perform the job they were intended for. And when products fail to do this, we want the companies to acknowledge the problems and fix them.
That's why I am so happy to report that Sigma had an issue of firmware compatibility with their lenses when married to the Nikon D5300. Clearly, the firmware problem is not what I'm excited about. However, the way Sigma acknowledged the problem and is completely willing to fix it is what I'm so happy about.
Without the latest firmware update, the OS and Live View Auto Focus functions do not work when a Sigma lens (with an internal motor) is paired with a Nikon D5300 camera.
The firmware issues of Sigma's Nikon mount lenses only affect those that already own Sigma lenses and have purchased a D5300 to use with those lenses. In that case, Sigma is providing a free firmware update service for those consumers. New Sigma lenses shipped from the factory will not be affected by this problem as they will have the latest firmware update.
If you already own the newest Sigma lenses and the USB dock, you can do your own firmware updates in the comfort of your own home starting immediately. Or, if your lenses are pre-USB dock (or you don't own one), you can take them to a Sigma distributor. See the link for locations. http://www.sigma-photo.co.jp/english/network/index.html
I am proud of Sigma for dealing with this problem so easily and quickly. I hope other companies take notice and do the same thing when they have problems--because problems are inevitable. Every company will endure them. That's just the way it goes. Trust is what we are looking for. As consumers, we simply want to trust the company we purchase from and know that they will stand behind their products.