Not having a clue about guns and picking up your first one at age 54?
I've been through 22 Gun transactions since 2013, including S&W M&P, various HKs, a Walther, and a couple Sigs before ending up with a Glock and a LCR, plus a bigger Glock I attempt to shoot in competitions. I think not having any kind of reference framework to evaluate both yourself as a shooter, or innate knowledge about guns, tends to accelerate the rate of change i.e. buying and selling.
Another component is how much patience you have (I have none) and whether or not at heart you are a "collector" or someone who wants a tool that they can get good at. In my case I value a gun that gets used, a lot, and I can operate, well. The problem for me as I started to accumulate that knowledge, I was always behind the curve, discovering or developing this or that skill that made the evaluation of the hardware different. As I progressed as a shooter, the factors I'd use to determine whether I was happy or not with a gun would change, I'd sell it, and the process would begin all over again.
Don't get me wrong, I enjoy working with mechanical things and the journey has been interesting to me and I've been able to have those different experiences. At where I am now, I am pretty satisfied I'm sitting in the middle of the least worst solution "for me" in terms of hardware, and I can now work on my software without changing carry guns every few months.