Snapchat used to be proud of its confusing design — the look made sense to its users, and that's the only audience Snap wanted. But now, after a disastrous earnings report that showed it's not picking up new users as quickly as expected, the company said Tuesday that it's planning a total overhaul. But it has no idea how it will be received. “We’re willing to take that risk for what we believe are substantial long-term benefits to our business,” said Evan Spiegel, Snapchat's chief executive.