exact same principle: if you're mining middle, clever etc. then you're indirectly mining for btc. Are you selling those btc for fiat right way?
you can sell right away and get the value now in $/£/¥/, or you can invest for a longer period of time.
if you're investing in btc for long term value, ignore the short-term profitability.
But if you're investing in BTC long term it will soon be cheaper to buy BTC from an exchange than run a miner. Im a noob and wasnt mining last summer but surely when it reaches that point you have to pull the plug.