Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What's happening? 
Shares of 3D Systems Corporation (NYSE:DDD) dropped more than 10% during Tuesday's trading after fellow 3D printing specialist Stratasys (NASDAQ:SSYS) issued disappointing preliminary 2014 results and 2015 guidance.

Why it's happening 
While it's tempting to think 3D Systems results -- which are due later this month -- will follow suit, that's not necessarily the case. Stratasys said its fourth-quarter 2014 results were primarily affected not by demand for its high-end printers, but rather by challenges implementing and scaling a new distribution model for its MakerBot subsidiary. In addition, Stratasys stated it "believes that Additive Manufacturing ... is poised to enter a new phase of increased adoption by manufacturers in a broad range of industries [...] by disrupting traditional design and manufacturing processes." As a result, its 2015 guidance incorporates increased investments to take full advantage of that impending shift over the next several years.

Over the long-term, that should bode well for the leaders in the 3D printing industry, which is why I'm convinced 3D Systems is being unjustly punished by the market today.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.