The companies which are making Linux Distributions are running on donation.For Example if all the peoples started using Linux Will this increase the income of companies which are making Linux? off course not because their income depends on donations instead of sale of their OS.But If more and more Peoples use windows then off course the income ofMicrosoft will increase and they will hire more experienced engineers and will make windows more easier.
2) Too many distributions, will they survive?
This is a very important question.As i have already mentioned that all the companies which are making Linux are running on donations.If they receive limited donation it will be very difficult for the companies to keep status of these distributions alive.
So why to have a risk that will you receive updates or not for your OS’s in future.Try a paid OS today and omit this tension from your mind.
3) Difficult to understand
If you compare Linux with any other OS like Windows or Mac OS you will find that Linux is too much difficult than other OS’s.For Example If you want to install a software in Windows or Mac OS you can do this by running a simple installer but if you want to install a software in Linux you will have to install it from a source.