There's a strong incentive to move quickly, too. The market has been tumultuous in recent months, and Lyft will want to launch its IPO while investors are in a spending mood. Another decline could make it significantly harder to raise cash, and might even prompt the company to delay or scrap its IPO until there are more favorable conditions.

The planned IPO might not seem too important if you have no investment plans, but it could be vital to Lyft delivering on its promises of more and more services. It hopes to dramatically expand its bike sharing and scooter offerings, and it still wants to add self-driving cars to its fleet. It only just started its first international service at the end of 2017, for that matter. Public stock could make sure you have these options in the future, and could make Lyft more of a viable alternative when Uber just won't cut it.