There could be more reasons to invest in cryptocurrency at a whole, but investing as it is has always been interesting, if played well. Nowadays banks hardly let you make money anymore and investing in crypto is the better choice.
Along with them, for common guys who do not understand that stuff, let me add some reasons why should one invest in Bitcoin. It is the future international currency controlled by no centralized authority so there is nothing to worry about the legal aspect. It is more liquid than your currency across the border. The risk factor is low and that is the reason why so many people are investing in the technology which has given supernormal profit to many and the up-thrust to the price of course.