Key Advantage of Open Source is ?

Computer Economics: research on strategic and financial management of information systems
Microsoft is as guilty as anyone of forcing upgrades whether they are ready or not in a way that makes everyone want to upgrade.
If you used the Office suite you would find that when you saved a file the default format is not backwards compatible. This primed the pump, if you will and made everyone think they should upgrade to keep compatible. Mind you these were simple text documents, or maybe presentations. I saw this some with CAD files as well, but the design market is much more polarized between Microstation and AutoCAD. With DXF/DWG in 12 or 14 as an acceptable middle ground for exchanging files.

More security patches inthe future, and maybe the customers will be less stressed out.

The survey indicates that IT decision makers value “reduced dependence on software vendors” as the most important advantage of open source. This indicates that software buyers must feel some level of dependence on proprietary software vendors, from which they desire freedom. Such dependence includes reliance on the vendor for maintenance and support and the necessity for the buyer to accept version upgrades that the buyer may not need or want.