Billings, which grew 10% in the July quarter, will be a closely monitored metric of how well revenue is expected to be as the year enters its last quarter. Bulls will disagree, but I believe aside from Fortinet's revenue growth struggles, it has been the company's weaker-than-expected performance in billings that has kept the stock from advancing relative to its other high-multiple peers, like Checkpoint. The other issue is that the security services industry has become highly congested with several new entrants such as Aruba Networks ( ARUN), which has begun to position itself for the growing demand of threat-prevention. And given Fortinet's current market standing and its strong reputation for quality, the company's products are often on the higher-end in terms of price. Consequently, with shrinking corporate budgets, IT leaders have shown a willingness to sacrifice quality for affordable pricing, which has impacted Fortinet's market share. By contrast, during that span, Palo Alto Networks ( PANW) has strung together impressive numbers, including 54% revenue growth in the recent quarter. To that end, absent a meaningful change in Fortinet's strategy to uncover ways to produce above-average growth and margins, I don't see any catalysts -- beyond an acquisition -- that will push this stock higher. Not to mention, the stock is already expensive with a P/E that is 4.5 times higher than Cisco and 3 times higher than CheckPoint. So, while I've always appreciated Fortinet's strategy of acquiring higher-margin business, management must now re-evaluate the effectiveness of that approach on the basis of these new entrants, like Palo Alto, for which profit is not yet a priority. They want market share. Couple this with Cisco's recent buy of fast-growing Sourcefire and it looks as if Fortinet -- as dominant as its products may be -- may remain a laggard for the foreseeable future. At the time of publication, the author held no position in any of the stocks mentioned. Follow @saintssenseThis article was written by an independent contributor, separate from TheStreet's regular news coverage.