The company I worked for in 2010 added a high deductible plan back then. I initially passed it up because we thought we were going to be having a baby that year and their HSA plan didn't make financial sense for expensive medical events like that. A friend of mine who was years away from having children enrolled in the HSA right away. By the time he and his wife had kids years later, he had enough to pay for all the expenses out of his HSA account and paid for lasik along the way. We've since enrolled in an HSA and it's worked well for us so far. We have enough in our account to cover 2x our deductible and are just shy of covering a years out of pocket maximum.
One thing I did not realize about HSAs until I enrolled was that you don't have to have 100% of the money to cover a specific event in your HSA account in order to get the tax benefits. If you start 2018 in an HSA with $0 and you break your leg on Jan 2, you can still utilize the HSA tax advantages. You would pay the deductible and costs out of pocket, but then you can pay yourself back with the HSA throughout the year. So, effectively, you still get the tax-free benefit of the HSA for an event that occurred when you had $0 in your HSA.