I suppose it depends on how much you're paying for electricity to get the BTC. If you're paying more fiat, than what you're getting back in BTC, it would be cheaper to buy the BTC outright. If you're gaining BTC and not exchanging to pay for the electric bill,  hold your BTC until the price goes up. At that point it's up to the individual, at what price range they want to sell. Everyone has a different situation, as we all pay different prices for electricity, and some people are on a long term plan. (Years not Months)