Pixar (NASDAQ:PIXR) shares dropped 7% on Dec. 8 because the company announced its next release, Cars, would be delayed until the summer of 2006 --from its original release date of November 2005. Many have speculated on the reason for this delay. My take is that it doesn't matter what the delay is, and I really don't care if I ultimately know the real reason or not.

Why the devil-may-care attitude? For starters, I don't own the stock. But more to the point, any investor who doesn't understand how long it takes to make a movie, especially a computer-animated one, shouldn't be investing in Pixar. Delays and moviemaking go hand in hand. As my first screenwriting agent told me, "Here's everything you need to know about movies. First, who's the director? Second, wait three years."

In the case of Pixar, it takes even longer to get movies from concept through script to completion. The most important thing to know about Pixar -- as is partially the case with Marvel Enterprises (NYSE:MVL) and DreamWorksAnimation (NYSE:DWA) -- is that there will be long stretches when they won't have movies. That's how the business works. Year-over-year estimates have very little meaning in Pixar's world. You have to find different ways to evaluate them, because of the peculiarities of their industry. We should only be concerned if we start to see frequent delays, especially ones without reasonable explanations.

Colleague Rick Aristotle Munarriz asks if Pixar's shareholders will be annoyed that throughput is happening three times faster at rival DreamWorks. I don't think that should matter, as I don't have any reason to believe digital animation is a zero-sum market. Even though more DreamWorks films means more overall competition, I think there's plenty of room for both studios and all the movies they produce between them.

Munarriz also asks how forgiving investors will be when Pixar "eventually coughs up a dud," and investors must wait 18 months before the next release. For what it's worth, I think the odds of Pixar coughing up a dud are pretty low, although it could definitely happen. But it will matter if Pixar's output decreases to one movie every 18 months and investors have valued the company based on expectations of cash flows from movies at 12-month intervals.

Investors looking for a solid and steady revenue stream from Pixar are looking in the wrong place. It's not their business model. But if it's quality movies they want, and they're willing to bet that Pixar's delays won't become too much of a habit, then their money could be well spent both in the market and in the theater.

Fool contributor Lawrence Meyers owns shares of Marvel Enterprises. The Motley Fool has a disclosure policy.