For some they cannot take volatility and require a comfort zone. Nothing wrong with that. I learned to take volatility having gone through a few major market turndowns, didn't sell, waited it out, bought low and have been rewarded. No risk, no reward.
"It came to me that every time I lose a dog they take a piece of my heart with them. And every new dog who comes into my life gifts me with a piece of their heart. If I live long enough, all the components of my heart will be dog, and I will become as generous and loving as they are."--Unknown