When I was at college, I volunteered to be the official vote tally person for student elections. I'd count up the paper ballot vote, (and recount, and recount again) and post the results publicly and inform the winner and losers.
One election, for senior class president, was very close. There were a couple on-ballot candidates and one popular write-in. It was not really very fun tabulating the results for that election, as the election was extremely close.
The day after the election I had a chemistry lab. A senior that happened to be in the same lab as I was talking offhandedly. She hadn't seen the results yet, and realized "oh, the election was yesterday. Whoops, I forgot to vote." And then she said "I don't really care about the results, except I really don't want Write-in-Candidate to win."
I told her, whoops, well, sorry you didn't bother to officially express your preference, because Write-in-Candidate had won by ONE vote. Yes, one single vote. If she'd bother to fill out a little slip of paper that was EASILY accessible to her living quarters, she could have at least caused a run-off between the leaders.
You think this is some one-off event? The latest governer's race in Washington state was decided by 129 votes, out of about 2.8 million ballots cast.
So look, go and vote. If your military can bother to go off and die for you, you can be bothered to participate in your own government at least once a year. Every single vote counts. Every one.
(ha, all votes count at least in a still-paper-balloted state such as Oregon. OK, not going there for now).