Considerations on O.S.S and property software

I was surfing on the internet reading artibles and watching some videos, and on my search, I found this one: Why use open source software.

After watching the whole video, I was impressed with how many information, we ignore about O.S.S and also on how wide and fast it's spreading the O.S.S. Considering that doesn't really matter if you feel agree with the usage of the O.S.S the facts exposed on the video are amazing, but we need to understand two facts before consider or think anything:

1.The video was a part of Linux company publicity on their products and services, one way or the other it's part of the video to "sell".

2.One of the most important components of the software, no matter what is to solve the clients needs, one of the most important is the cost that software could have, there are may activities that must take place and be executed properly to generate software with the needed level of quality.

Considering this is clearer to see that you must think first on the clients needs or even your own needs, at the time you want to choose between the O.S.S or the property software.