It is always worth it to mine btc as long as you don't mind the sound of the machine and/or you are okay with using your electricity bill as a credit card on which to purchase btc every month.

That's how I look at it. I used to have a 2 THs miner plus my S3 miner going and all through out 2015 - 2017 they mined fine. The 2 THs miner was loud as all hell but I put it in the garage so it was okay. But then an angry neighbor smashed it lol. Anyways through that time I never once thought about shutting them off. ( It was to much fun mining ) And the electricity at the end of the day was manageable.