Most in here delude themselves by seeing their fiat profits going up, so they don't feel so bad by losing coins.
I'd say that:
a) more than 5 trades per month is reckless, considering the high fees + slippage.
b) the only good moment to trade is a bear market - and there's is no bear market ATM (this could change in the next days/hours, but I wouldn't bet on it).
That depends entirely on what your stance is.
If you are in it to make profit in USD (like 99% of this market is doing atm), day trading to get USD gains is perfectly fine. And I say, in a market where there's currently (and practically always) the looming danger that the value of BTC goes through half, securing FIAT profits is not that bad an idea.
If you are a utopian true believer in BTC, believing it will go to 1 million USD per coin no matter what, yeah obviously don't sell then.
Even as a true believer in bitcoin believing that it will go up to at least 6 figures, I'm still going to sell some long before that. I'm not a fool.