I see this is an old topic but here is my side of this: I started Warframe for free a year ago and got bored after 10 hours because the game fails to tell the story. Then I bought Destiny 1 with all the DLC (yes, in 2017) and really very much enjoyed it with a friend until I earned 393 light. Then Destiny 2 arrived and I bought it expecting it to be even better! I bought the deluxe version with two DLC included. The game was a flop. Too easy. Not fun any more. Never played the second DLC, sold the PlayStation. At some point in time Warframe announced Plains of Eidolon open-ish world story and this is where it got me back. Now I have 60 hours into Warframe and the stories only just begun. Warframe definitely grows on you and you don't really have to pay nothing if you don't want to. It's even more fun this way because when you pay for stuff then you have less to do in the game. I love Warframe and I will play it until there is content.