Trying a demo is not bad but remember that you won’t have a first-hand experience with re-quotes and slippage. This is something you’ll experience when live trading.
I have been trading with short term trading plans for the last 2 years and I can tell you how well they work. I am not so much of a long term goal oriented person so this strategy has been working for me.
I’ve seen brokers claiming that their demo accounts are as real as their live ones but the truth is most of them are just a projection and are not always accurate.
You’re right. Saying this after spending and wasting months practicing on a demo account only to realize that the spreads quoted in the live trading are much wider as compared to the tighter spreads that made trading profitable in demo.
I hardly believe demo accounts give a real world trading experience to the beginners. And moreover if one’s spending time and months learning tricks of the trade, why not go live trading?
I don’t think everyone benefits from demo trading because it fills you with hopes and when you go live, you don't get anything more than disappointment.