I like Under Armour Inc (NYSE:UAA) as a company. I really do. The story of CEO Kevin Plank’s rise from University of Maryland football walk-on to S&P 500 CEO is a great tale. The problem is that alone isn’t enough to buy UAA stock.

Sure, Plank took Under Armour from an upstart company with zero sales to competing with behemoths like Nike Inc (NYSE:NKE) and adidas AG (ADR) (OTCMKTS:ADDYY). It’s an impressive accomplishment. Still, not convincing enough to own the UAA stock right now.

At the moment, UAA stock finally has settled down, below and near $20 since late January after an ugly 2016. (The Class C shares, ticker UA, are a bit cheaper, a premium that still offers an arbitrage opportunity.) But, not cheaper enough, or even close. A 48x multiple to 2018 analyst estimates prices in a tremendous amount of growth. And I remain skeptical that growth is on the horizon for Under Armour.

Under Armour Gets Back to Basics

To his credit, Plank has responded to the decline in UAA stock by promising to improve Under Armour’s operations. At the shareholder meeting earlier this month, the CEO reiterated that the company was focused on execution and getting the product right.

In a retail space where far too many CEOs have chalked up weakness to unspecified “market challenges” or other supposed headwinds, Plank’s honesty is refreshing. And if Under Armour can execute on some of their ambitious plans, UAA stock (UA shares, too) probably do have some upside — at some point.

International penetration is limited. The women’s business hit $1 billion in sales in 2016, but Under Armour has larger goals for that channel. Despite the doom and gloom around UAA stock, the company is still expected by analysts to drive double-digit revenue growth in both 2017 and 2018.

Solid execution and operating leverage should result in even faster earnings growth. If Under Armour can get back on track, UAA looks like it should be a buy.

UAA Stock Isn’t Cheap

The problem remains, however: Under Armour shares are too expensive.

Better execution and decent revenue growth simply aren’t enough, as I’ve argued before. At that 48x multiple, Under Armour needs earnings to double to drive real upside for its stock. That translates into 10%-15% revenue growth and a few basis points in margin expansion, which will take four years at least — assuming all goes well.

The other issue that’s become clear of late is that there are a number of factors beyond Under Armour’s control. Indeed, the tight trading range for UAA stock over the past few months looks like a battle between optimism supporting a turnaround at Under Armour and pessimism about its industry as a whole.

UAA stock fell 4% when Nike ‘reset’ its go-to-market strategy. Reports of the retail entry by Amazon.com, Inc. (NASDAQ:AMZN) also shook Under Armour stock. Meanwhile, new distribution agreements with Kohl’s Corporation (NYSE:KSS) and DSW Inc. (NYSE:DSW) seem to have had early success. But those agreements tie Under Armour to two companies whose fortunes appear to be waning.

Consumer tastes change — another potential headwind. Raymond James reiterated an Undeperform rating on UA and UAA stock, pointing out that consumer tastes were moving toward fashion — and away from Under Armour’s sweet spot.

And, of course, there’s competition. Nike and adidas aren’t going anywhere, and even Puma is seeing revenue growth. Under Armour is going to have to battle Lululemon Athletica inc. (NASDAQ:LULU) in women’s lines.

Under Armour can, and likely will, execute better. But if the economy turns, or when fashions change, or competitors up their game, that may not be enough. And given what UAA stock is pricing in, it has to be — and then some.

As of this writing, Vince Martin has no positions in any securities mentioned.