There are two things that matter when building great products, movements or companies. They are easy to follow, easy to understand and also incredibly easy for those of us with MBAs and too much corporate experience to screw up.

• User scale
• Forgetting the non-believers

User scale is not about scaling to allocate your fixed costs over a larger user base. Or scaling revenues, advertising impressions or distribution channels. Great products, movements, and companies are created when the number of end-users expands exponentially. I was reminded of this by yesterday’s GigaOM article on YouTube.

YouTube users now upload 72 hours of video every minute to the site, up from 48 hours per minute last year and 24 hours in March of 2010. The explosion of content is mind-boggling and it matches a pattern we’ve seen again and again with Facebook, YouTube, the civil rights movement, the spread of most current major religions and the pet rock.

What drives user scale? Again, pretty simple. Good ideas. The idea that you could share your daily comings and goings with friends via Twitter is a good idea, as was the idea that you could show your hipness by carrying a pet rock or wearing a mood ring.

Good ideas do not include: How can I drive the stock price? How can I keep this machinery running 24×7? How can I cross-sell $10/month more to 5% of my installed base? MBA ideas, all. Do you think Gandhi overcame hundreds of years of cruel British imperialism by worrying about his installed base?

Forgetting the non-believers is the second critical component. This morning Seth Godin reminded me of this by recommending that we “shun the non-believers.”

Not everything is for everybody, even pet rocks. So why do you care what the naysayers think? Your idea isn’t for them. Fine.

There’s another group of non-believers you also have to forget about. It’s your own internal folks. They look like they might share your cultural beliefs and norms, but are still threatened by your ideas. Your idea might put the current company out of business. Or you (or them or your team of MBAs) out of a job. Since they’re not going to help you, why do you care what they think?

Takeaway: Good ideas, companies and concepts scale users quickly and tend to alienate non-believers. Do those to make great things.

Or keep making undifferentiated beige boxes of mediocrity.