Shares of lululemon athletica (LULU 0.52%) are down more than 10% today, despite the company meeting revenue expectations and exceeding earnings expectations this past quarter. Motley Fool One analyst Jason Moser thinks the reason for the dramatic decline is the company's forward guidance -- Lululemon guided modestly downward for top-line sales. But Jason thinks investors should be more worried about Lululemon's production issues, which have hurt its margins, as well as heavy competition. Jason doesn't think today's the day to buy Lululemon --he doesn't like that it's stuck in a niche and doesn't have as much of a market opportunity as a competitor like Under Armour (UAA -1.73%) may have.