You are right that Bitcoin is the best investment. Most of the major investors in the cryptocurrency market invest most of their money in Bitcoin and if you invest in Bitcoin and are not able to hold it for a long time then your investment will have no value. So before investing in Bitcoin one should have a long term mindset and then invest.
Bitcoin is the most reliable investment among all the cryptocurrency, Bitcoin gives you rest of mind when you invest into it because you can't lose unless you sell your coin below the price that you bought it because of fear as the market starts to correct. Bitcoin gives profit to those individuals that have patience and are willing to hold Bitcoin for a very long time. You can make profits in short term when you invest into Bitcoin but it can't be like the profits of someone that didn't sell early and was holding as the price of Bitcoin keeps increasing. Bitcoin is the best investment and also the best currency right now therefore selling your Bitcoin too early isn't a wise decision. If you don't sell and continue holding you can sell your one Bitcoin for more than $1 million in the future.