This implies that, you must always leave a little fraction for probability of failure which in this case is the safety factor, no matter how little the fraction may be. Simply put, you don't have absolute control of what happens to Bitcoin and Cryptocurrencies in the future.
Invest wisely, only invest what you can afford to loose
Just a piece of advice.
What are your own suggestions?
Yes, I really agree with you. I personally see that all of this is competitive and there is no guarantee of profit. But, all depends on each individual to make an evaluation of the costs and risks that may arise.