In all, it is an individual thing and depends entirely on your plans.
if you have a target you are not supposed and if the target is met then you can sell, but not everybody has the patience to wait for when the target is met, and always waiting for the price to come low is not always the best, what if the price does not come down, it will not be favorable if you buy high and still sell high that is a very poor business mentality. I can sell during bull and the only thing I will be selling is my profit and not my capital
and even during bull and not selling I just wonder what else the person is looking for after making a profit is there anything again, but everybody has their own decision over their assets?
that is the purpose of investing when the bear market is over then after a very long wait you can enjoy the fruit of your labor, yeah since it is a free world people have the right to decide the faith of what happens in their investment. the profit can sustain the investor for some time, and once the profit is made it should be wisely used because these days it is very difficult to keep money these days you can even re-invest the money.
People who have steady incomes don't bother much about their investment, since they have another means of earning which makes the investors more financially stable in a way, In 2019 a lot of people cashed out buying at 5000 and bitcoin hit 60k a lot of profits. some investment should not be underestimated.