Software reliability is key to the good health of your website. To assure reliability, you need protection from arbitrary and unwanted changes or abandonment of software leaving you without support

Proprietary commercial software may not meet your needs. This is especially likely if you have unusual or specialized needs, or if you consider stability more important than new features.

Free software gives you more control over the software in your website than proprietary commercial software does. Free software allows you to control your software upgrade cycle to meet your own needs. It also allows you to customize the software to meet your special requirements.

A good practical test of your control over your website software is to attempt to have a bug fixed or a feature added by someone other than the organization that provided the software.