Our company is blessed with many unicorns. In our company context a unicorn is somebody that has been in the company for ten or more years. From our a bit over 100 employees a whopping 20 % are unicorns! This came up when I finally decided on my unicorn gift which I became entitled already back in last August (we get a gift of practically anything we want up to a certain amount as a thank you for being so long with the company).
Even for a mythical being the unicorns are one of the rarest. But with so many unicorns in our company we might need to come up with something even more rare for our next step in our loyalty program.
It's not that common, especially in this industry, to have such long careers within one company. It feels like most of the people around are switching jobs every 2-5 years. It's usually the best way to progress ones career and get better salary.
I guess we have kept our salary levels quite competitive and offered good opportunities for people to step up on their career. But I believe the big part of making people stay is the culture and the people themselves.
Oh, and the collective noun for unicorns is blessing of unicorns. Just like their marine, real world counterparts the narwhals.