Proprietary software and hardware that keep secrets behind closed doors can cause a lot of headaches. Proprietary software in particular is purposely kept secret by the organization in control of it, in order to give themselves leverage and also to "protect" the software, in their opinion. However, this can cause a lot of headaches for the end consumers using the software. For this example, I'll only discuss product support. All product support for proprietary software is normally funneled through the vendor company itself, as there are usually no ways for 3rd parties to support the products since they are proprietary and kept behind closed doors.
The consumer is often forced to go to the company in control of the source code for any problems. This can make it very costly because the company in control can charge just about any fees they deem necessary. I've been faced with situations where a company demanded an outrageous hourly rate, equivalent to those made by a lawyer. And since we were locked in, we had no way around the situation, we ended up paying for about 2 hours of support (which was also their minimum). Other similar schemes are support contracts that the consumer must pay an annual subscription for, yet sometimes the support contracts aren't even used, which results in money thrown down the drain.
Another common problem is when trying to contact the company for support, the consumer can experience extremely long hold times on the phone or also have little to no success in getting through to anybody. I've been in a situation before where the support line went to voicemail, and after leaving multiple messages we could not get any responses. We had already purchased the product, so we were stuck. Eventually we managed to get through, after quite a bit of wasted time. This activity is all too common now, where you get a great sales pitch but when it comes time for support of their product, it's practically nonexistent. The consumer could end up taking the company to court, but consider the amount of work and wasted time that involves.
And there's the fatal situation where a company that previously released software completely goes belly up, bankrupt, or just fizzles away into existence. This is the worst scenario, as all support is basically dropped completely, unless another company comes along to buy its assets. But, even then it can still be a mess with knowledge transfer among the two companies, etc.
So in the end, consider the tremendous benefits of open source software. The code is not owned and controlled by one entity. This means the community itself can support it, which opens the doors up for all of us to share it. Best of all, it often means the product is also free of charge for the original purchase, and for support. Sure, you won't get phone support or direct one on one support that you can still get for some proprietary software, but do you really need that type of premium support? With message boards, wikis, IRC, and other forms of excellent support methods of open source, the old fashioned phone call or even email support seem like old methods.