The maker of sensible sandals has been around for 250 years. So why did it go public now?

Birkenstock shares started trading on the New York Stock Exchange on Wednesday, pricing its IPO at $46 per share.

The supportively soled shoe brand is the latest company to file to sell stock to the public after a long IPO drought. The move indicates a stable, confident market.

It takes more than trends and nostalgia to become popular a second or third time around. It can take years of hard work.