"Stay away from negative people. They have a problem for every solution."
There is a danger in assuming there are people we can consider "negative people" who possess a destructive trait, when it's likely that we all exhibit negativity from time to time.
Each one of us can fall victim to the mental attitude of finding a problem in every solution.
"Oh, but that will never work, because of..." and we pile on the reasons for why it won't work.
But everything that has ever worked in the past was met with resistance early on, because everything is open to the possibility of not working and the risk of failure.
One of my favorite quotes in the startup world is about Wikipedia which is described as a concept that "works really well in practice, just not in theory."
If it works in practice but not in theory, then the theory is flawed, and whoever denied its chances of success was unable to see its true potential and misjudged people's willingness to contribute, for free, to a cause they believe in.
With every project you want to undertake, or any design you make, or any thing you want to accomplish in life, there will be obstacles.
Instead of asking yourself: "Will it work?"
Ask yourself: "How can I make it work?"
Then make it work.
You may have to adjust your approach, but you won't know until you try. You have to be committed to succeed rather than find excuses for why you failed.
How can you make it work?
Now make it work.