As a non musician that wants to learn to play an instrument, it seemed like a no brainer.
Harmonicas are not as expensive as other instruments, they do not take up a lot of space, and you can carry them around with you. I can play around with it in the evening when the kids are asleep, or while stuck in traffic on my commute.
How much would I spend on a guitar, or brass instrument? I have always had a thing for pianos, but they are larger and cost more than I would like to spend on what can ultimately just be a phase of mine. Much easier to justify a $40 harmonica. If I feel I have aptitude for music and enjoy it I can always get a guitar or something else later.
There is also something special about the Harmonica. It always seems cliche when one of my colleagues mentions they are learning to play the guitar or drums. I always think, “typical new dad trying to stay cool”. It seems a bit too much like one of those Rock Band video games. I also do not have that fear of being compared to little girl that has been taking piano lessons since she was five. A man in his thirties playing “here come the clowns” on the piano is not what I want to be associated with. Playing row, row, row your boat on the harmonica just feels less embarrassing.
Harmonica felt more original and solo to me. I have not mentioned it to anyone, but my wife of course hears me play.