Even if the bitcoin reach 20k USD at the last December 2017 , people will still have a doubt on it because the price of bitcoin is now on dip, and I believe that if we don't have a faith on it we maybe afraid to invest on it today because the price is slowly dropping and it seems like it almost drop every now and then. So many small investors are now afraid of it. Because they can maybe lose or earn on it due to the huge dip.

What you have identified here, is the current trend of bitcoin market. However, what you think about the bullish trend, is your own thought only! It has no actual ground and not based on facts. It is a speculation that you have made.

Surely I want bitcoin prices to go up because I will be profitable if it happens. But what I see in the market is mostly a bearish trend! If you compare the price patterns starting from March 2018, the trend will be crystal clear to you!

Yes we don't have to make doubt on it. Specially on this dip we really need to buy more bitcoin before its too late and we can't afford to buy it. Bitcoin will not giving more opportunity in the near future it will possibly become a big thing in crypto and it's price will maybe rise up high. So then before that time comes that by will rise and we can't afford to buy it we maybe need to make buy in it today for good.

Yes. We should never entertain any form of  doubt concerning bitcoin investment no matter how bad we feel the market may be.

I will give following advice: Never invest money you can't afford to loose.
Yes, bitcoin is great but we never know what future may bring.
Please guys, be smart and careful.

I don't doubt you in anyway. It is very certain the crypto market prices will increase again. What we are just hoping is for it to happen as soon as possible to stop the fears in people.

I guess more peoples will doubting cryptocurrency if the current price keep staying on the bottom or getting worse, thats why they see crypto, by the value on the market. For me, this kind of market is only temporary i know it. The peoples sold their coins will buying again later, then the market will recover. And in if the future there are more peoples and companies using crypto, this price won't be seen again

Only way BTC goes to $4K is to bleed out the rest of the alts/shitcoins. BTC seems to be in really good shape around 6K. Just waiting for every other alt to die off (same at DOTCOM boom) so one will raise again. BTC is the "stable coin" everyone is searching for

I disagree.
having doubts when it comes to investing your money, specially in new technology, is a natural thing. people should have doubts and question everything. and bitcoin investment is a risky one. but the important thing is what you are doing after having those doubts. for example a newcomer is reading and believing the FUD instead of reading the reliable sources about bitcoin and educating himself about it then he is doing the wrong thing.

in fact that is one of the biggest problems that people usually have, and based on your last sentence I would say you also are making the same mistake. you don't educate yourself and are too caught up in making profit that you think the "whole crypto market" will go up be cause bitcoin is a good investment.