What the reason
What the future waiting for you
Here is my input from all of your questions.
Mainly what the purpose -> If you are asking what is the purpose in accumulating a bag hold of btc the the straight forward answer to this is that this would be used for future purposes once it is fully accepted in the society. Meaning it can be used as a means of payment for our daily needs.
What the reason -> The reason why we wanted to accumulate or why we choose btc? But to to cover both question the simple answer is that btc is a good investment and that's it.
What the future waiting for you -> Honestly no once can tell what the future holds for btc but this is what makes crypto enticing. The future is uncertain and exciting at the same time.