Your buttons messed up?
There are a couple aspects to the sleeve buttons on your jacket, how they are sewed on and if they "work."
Working/Functional buttons are really called "surgeons cuffs." It is unknown when they first were invented, but the reason- it was a way for the military surgeons to roll their sleeves up on the battlefield and repair their fellow mates.
You obviously will not be performing any spur of the moment surgeries, but, the craftsmanship of working buttons usually dictates a detail only found in custom.
When I was selling high end retail suits, adding working buttons to the sleeves cost up to $150 (on top of an already 3k suit), this always irritated me. Now knowing the back end up things, the expense at production level is only a fraction of that cost- something that I personally don't upcharge for at all.
Rarely you will see stocked suits and sportcoats with working buttons. The reason, you can't alter the sleeve length. Unless those sleeves fit great off the rack, it won't work for you. Typically because of this, the power of numbers suggest the retailers sell non-working buttons so more people are able to buy it.
I do need to clarify one thing specifically about surgeons cuffs- they aren't missing a button!! So many people say "Is that missing a button?" Some people say its correct etiquette to unbutton the last sleeve button when you have working buttons- but that is only to show they are working. Whether you unbutton it or button it- either is fine. If you do choose to unbutton one, it HAS to be the last one- disregarding where the colorful stitching may be.
Are your buttons kissing or flat? Most people either aren't aware of these two button positions, some even think they might be sewed on mistakenly. Lets clarify:
Kissing buttons overlap each other (also called "waterfall" buttons). It's more prominent and inherited from the Italian suiting's- where tailors would ever so slightly sew on the buttons with imperfection, denoting the suit is hand tailored. They are typically stacked on one another, and its one of those small details where people might say "that is a well tailored suit."
The "flat" buttons are when buttons are spaced apart and not touching each other. There is no right answer to what buttons you choose, it is purely preference. I personally always do the kissing buttons- but again, you can decide for yourself.