That it has to be written.
The reason I vaccinate my kids (and kudos to the OP for being able to spell those diseases) is simple: upside > downside. In this case, upside >>>>>> downside.
Which is why the annual flu shot is not among those vaccines. The upside and downside weigh out fairly similarly. With the flu changing drastically every year, herd immunity is so short term that I'm doubtful that there's much immunity to be had there anyway. For otherwise-healthy kids and adults, it's not really that severe.
Everything else, polio and all those other ones I can't spell, except for maybe the chicken pox, even the smallest infection can be devastating. (Pox's worst infections can be devastating.) It's not uncommon for any of the rest of these diseases to kill or maim their victims. Risk of disease (small) times expected outcome (really bad - killing or maiming) compared to risk of shot (high) times expected outcome (short term pain, soreness, tiredness, going away in a day, give or take, treatable with tylenol). Yeah, that's a no-brainer.