In my humble opinion mining protects you (mentally

) from the BTC/USD price drops, as long as you have very cheap electricity.
You get returns during the bear market, even though they're small, but they are constant, although declining over time.
Generally, not too many miners join during the bear market, so you can collect substantial bag of BTC over time.
Later, when the price is high, you have the coins and the gear, which you can sell for double the price it cost you to buy.
As others mentioned - taking good care of the gear is the key, as it can suddenly break. But it is also usually not very expensive to repair in a bear market.