I used to think that confidence is something you gather over time. That with experience or success you could accumulate confidence, and with embarrassment or failure, some of it disappeared. More recently, I've discovered (or maybe I've decided) that this is not not how it works for me.
I have days or hours or moments when I don’t feel confident or sure of myself for no reason. I wake up, either literally out of bed, or figuratively from some other stupor, and feel weak, unsure, and like it’s best to keep to myself. On some occasions I try to speak and am horrified at the squeak that comes out. On the other hand, I’ve seen days and hours and moments when I feel in control. Of every limb in my body, of my voice, my words, of every variable around me.
These variations seem random, to say the least. To explain them, I need a new model to explain confidence.
Rather than thinking of confidence as something that grows linearly over time like the stock market and corrects itself at unpredictable intervals---also like the stock market---maybe confidence is like a light switch: either off or on, but only off or on, and nothing in between. You wake up and it’s on, and you’re ready for the world. You snap out of it and you wonder what even gives you the right.
I find it useful to think of confidence in this way, because it means that when it's off, there's less pressure to turn it back on. It doesn't feel like I'm sliding down the hill that I worked really hard to climb up. That's comforting. I know that when the switch comes back on, I'll be as strong as I was before.