We can all agree that a working boiler is a necessity when the weather is out of sorts, and all you can do is dream about walking into a warm, welcoming home.
It is also nice to have hot water because of creature comforts and all that.
In all seriousness, though, even though boilers these days are very reliable and will last for years, it is still a good idea to have them serviced regularly.
Honestly, it should have a spot on your yearly home maintenance checklist.