In this video, Motley Fool tech and telecom analyst Andrew Tonner outlines three reasons to sell Nokia (NOK -0.27%). First, the company is betting its survival on the success of the Lumia smartphone line and Windows operating system. If Lumia doesn't fly, Nokia likely won't either. Second, the company still experiences revenue declines despite restructuring. Cash flow has improved, but if revenue declines continue, cash flow will likely suffer, too. Finally, Nokia is trying to reassert itself in a market dominated by Google and Apple. These companies enjoy strong customer loyalty. Nokia faces a tough battle to win over these customers.