The problem with art is that it's a subjective medium that, through its very nature, invites comparison. You listen to one song and think it's pretty good then listen to another and like that one even better. Then you find someone who thinks the opposite. Then you find someone who thinks both songs are trash. All the while the ones who wrote those songs may never have even heard of each other—may never have even been alive at the same time. Neither would have ever imagined they'd be in competition, yet, years later, there they are, as a result of conversation between people they've never met.
As subjective as art is, consider J. R. R. Tolkien and C. S. Lewis—specifically, The Lord of the Rings and The Chronicles of Narnia. If one of these is better, it's going to be The Lord of the Rings. Lewis would've said so—even Tolkien, if pressed. Lewis and Tolkien were friends, they encouraged each other as writers, they shared ideas, their works have similar themes—you can see the influence in both works—but if you had to choose one, it's The Lord of the Rings, hands down.
But does that mean The Chronicles of Narnia is worthless?
There are tons of people who've read and enjoyed the Narnia books over the years, and I'd say a sizeable portion (myself included) who never knew until much, much later that Tolkien and Lewis knew each other—that the two series had anything to do with one another. Something which seems terribly relevant at one time may be all but forgotten at a later date. (For example, did you know the Beatles and the Beach Boys had an intense rivalry in the 60s? I didn't. I'd heard about the Beatles and the Rolling Stones, but the Beatles and the Beach Boys...? I doubt if I ever realized they'd even heard of each other.)
It's a difficult thing to do, I know, but if you have an idea—a drive that pushes you toward some artistic goal—you have to follow it while you feel it and then evaluate/revise/edit it later. You have to let the thing be what it's going to be. When something is new, the unfamiliar are going to see it as strange, and may offer you suggestions on how to make it look more like something they're familiar with. That may, indeed, help it be more recognizable and more acceptable to a current audience, but it may be robbing the work of an opportunity to be unique and original.
Going back to Narnia, consider the world building in the first book examined through the lens of Tolkien. My, but it looks sloppy! I mean, there's a random ass lamppost in a fantasy world? Fauns are there, as well as talking animals, and then…Santa Claus?! Santa Claus?! And the Tolkienite is asking how all these things tie together, what exactly the nature of magic is, what land Santa Claus hails from, how he interacts with the "real" world, etc. From the perspective of hard world building, you can imagine someone saying to Lewis, "Hey, maybe consider pruning literal Santa Claus from the book. It doesn't make sense." And if he didn't hold fast to his vision, maybe he does that. Maybe he also tightens up some of the other looser aspects of the world building. And maybe the end result is something a little more Tolkienesque—and, essentially, not at all The Lion, The Witch, and The Wardrobe.
I took a course on Samuel Beckett (author of the play Waiting for Godot) and we read almost all of his work. He started with novels. He actually served as transcriptionist for James Joyce's Finnegans Wake when Joyce lost his sight. His first novel, Murphy, reads like someone who's trying to sound like James Joyce. There's definitely Beckett in there, but it's like he's trying to take his vision and push it through a Joycean mold. Now, there's nothing wrong with James Joyce, of course—he's one of the greats—but he's not Samuel Beckett. And it wasn't until Beckett loosed himself from these shackles that we saw what it was he could do. And, truly, he went on to produce some stuff that no one else could ever have produced (cf. Worstward Ho!). It's not necessarily better than Joyce, but also, Joyce isn't necessarily better than Beckett. Truly, it does not matter. Each of them produced something truly unique—true to themselves—and the world is better off for it, whether you like one or the other better, both, or neither. (Incidentally, this is another of those pairings that may surprise. Did you know Samuel Beckett literally transcribed Finnegans Wake for Joyce late in Joyce's life? I didn't, until that class I took.)
Back to the point of the post, there are two things I'd say:
Yes, your work may not be as good as someone else's. Chances are your work now isn't as good as your work five years from now. So? If you don't do what you're doing now your work five years from now won't be better. You can look at my early language work. It's not as good as what I do now. If I didn't do it, though, I wouldn't be where am I now. Oh, and you know what? At the time, I thought my work was fucking incredible. I was wrong, but sometimes if you don't have fans, you have to be your own fan to get you to where you need to be.
Yes, your work may not be as good as someone else's, but that doesn't mean it doesn't have value—and not because you're going to get better later because of it. There's someone out there that may like the work you're producing right this second just because. They may love the sound of it. They may love your unique twist on a case system. You may look back on the work you're doing now ten years from now and say that it is objectively shit, but then ten years after that someone on the internet will find it and say they love it, despite what you think. That's art. That's audience.
Most importantly, you can't let the voice inside you cut you down before you've had a chance to do what you're doing or else you'll do nothing. When negative thoughts come, you acknowledge that they're there, and then you tell yourself that it's just talk. Don't ignore the negative thoughts: shine a spotlight on them. Recognize that they are thoughts, and as thoughts, they can be pushed aside by something as insignificant as a damn commercial jingle you can't get out of your head. Some of the vilest thoughts I've ever had—crippling self-doubt, negative self-talk—can't even go ten seconds in the ring against the fucking "You won't get a lemon at Toyota of Orange" jingle that's come back to me at odd moments every day since I first heard it in 1987. Some musical hack that I hope to beat to death one day created a five second jingle that has spent more time in my brain than some actual humans I love and adore, and, believe you me, that stupid jingle is way more powerful than any voice in my head that says, "You're worthless trash"—and if that's true, how pathetic is that negative self-talk? What power does it really have over you?
Sometimes comparison helps. Sometimes it helps you grow; sometimes it gives you new ideas. But it has its time and place, and that time and place is not amidst creation. That time is your time, and I'd encourage you to let it be just that: your time to create.