When Nike (nke, +0.09%) recently announced it would start selling on Amazon after years of hesitation, some saw a potentially brand-damaging move. But the company needs the e-commerce giant’s help to make good on a bold promise it made two years ago: hitting annual sales of $50 billion by 2020—a 67% jump.

Though it’s thriving, Nike is facing a resurgent Adidas and a growing Under Armour, not to mention a retail environment that is “not in a steady state,” to quote Nike CEO Mark Parker. Wall Street analysts expect Nike sales to hit $42.5 billion in three years’ time, according to Bloomberg. That’s impressive, but well off the shoemaker’s original target.

Nike is hardly the only company now finding it hard to meet its own lofty projections. In February, Nestlé, now grappling with an activist investor, said it was taking a “timeout” from its long-term…