Well, no one knows if they would win the contest or not. The fear of losing should not stop you from trying.
As you have mentioned that their friends account creation on roobet and bitcointalk depends if they are able to win the contest does not seems right as no one knows in advance who will win the contest. I guess everyone who have designing and creative mindset should try their luck in these competitions which are rare on this forum. Thanks to Roobet for providing this opportunity to us.
How it's possible for his friend to know if they are able to win or not because most of participants are submitting their entries in the last 1-3 days As you have mentioned that their friends account creation on roobet and bitcointalk depends if they are able to win the contest does not seems right as no one knows in advance who will win the contest. I guess everyone who have designing and creative mindset should try their luck in these competitions which are rare on this forum. Thanks to Roobet for providing this opportunity to us.
I don't think someone can create a good art for 1-3 days only because you need to prepare anything about the concept and idea which can take a lot time, not to mention everybody have daily routines and busy.
Joining an art contest doesn't only make you earn the prize if you win, but it can improve your skill and portfolio which you can use it for freelance job.
Otherwise, if the reward was as low as what designers normally charge, then only amateurs would join, but since it pays more than what anyone would charge for this, it becomes something more valuable and worthy of participating. Nobody forces anyone to join, if you want to do it then by all means you should give it a chance and see if you can win, if they don't want to, then don't.