Since I see that you are a noobie. Iam going to reccomend you do not do this.
Search up how much the difficulty rises on coins. You will see it is very unprotittable to mine coins. It is almost always better to buy the coins right now and hold them for awhile.
With mining the difficulty goes up every 7 to 10 days for bitcoin. Say the difficulty goes up by 10%, your 100TH miner is now only mining at 90%. Next difficulty happens, now your 100THs is like 75%.
What I am saying is, when you have 100TH and difficulty goes up, it is harder for your 100TH to get the same reward. If you were getting .1 BTC every day you are now getting .09. Next update happens you are getting .075, then .06 then .045 then .033 then .02. You usually will lose money due to this. Each time difficulty goes up your reward goes down, which means you have to keep buying mining equipment. Your electiricty cost will soon become more expensive than your mining profit because you don't live in china where it is cheap.
you are pointing it to altcoin, but he is talking about bitcoin mining, and no it's not unprofitable to mine bitcoin or altcoin, otherwise no one would mine
it's the opposite it's more wise to mine than buying but not everyone can do this so there are investors, if the diff go up it's because there is a huge margin on profit currently, with the very high value of bitcoin
the bad thing about asic mining is tht you need to stay always competitive by adding other asic, with gpu is different you can stay there with 1 rig forever and have the same earning