Saving money in the bank will get you somehow a small interest but still it is a very small gain. But if you are going to hold your bitcoin to your btc wallet there would be a moving in the price the bitcoin also that you are holding will increase, if the price increased, but if the price decrease. Your btc also will increase.
And saving money will be always good so if you want to earn more money later than you have to make an investment.
I agree with that fact, investing with bitcoin by means of trading will really get a you an absolute profit if you are good in trading but still there are other ways of investing of money you just need to have a trusted people for it.
Having a saving while on a investment a really good back up to your financial.
I think physical investments are better then online investments, there is a trust and belief that you will not get cheated, but online investments cannot be trusted as majority of them are ponzi.