If you have cheap electricity, maybe. Electricity at $0.05 per kilowatt-hour or less is ideal. Unfortunately it might be impossible to recover the cash used to buy the miner. I read an article where the money used to buy miners could actually get a higher profit if BTC were bought directly as the value of BTC rose. Therefore you might want to consider just buying the BTC instead of spending the time, money and effort trying to mine.
You are practically understood the process to make profits on smart way. As you said instead of buying miners and run with electricity cost. We can invest that money in multiple ways like in bitcoins and altcoins as well. Do you think we can't ignore mining for altcoins because am not sure how it gives you hands and it may helps to earn something. I hope you had a very practical experience and some impacts on mining. I will think about investment anyway.