The thing about limits is this: it's okay to have them. It's even desirable to have them. The word for healthy limits is boundaries. Knowing your own limits might be one indication of having good self-awareness. And if we want to talk about the external limits the world imposes on each of us—because it does, in one way or another—well, knowing what they are is just smart. That's the only way we'll ever push past them, if we decide it's worth it to try.
I am never going to be an author who publishes four books a year. I don't have four books a year in me, and honestly, I no longer want to. That's not for me. Even if I were single and childfree and had some kind of independent wealth that also came with health insurance so I wouldn't have to work just for the insurance, I wouldn't write four books a year. (Please note that I am not saying there is anything wrong with writing four books a year. It's just not something I am capable of, and I accept that about myself.)
I put limits on my writing life, life puts limits on my writing life. And that's all okay with me, because, to paraphrase Louisa May Alcott, "The books don't love you back." So there are many things besides writing on which I choose to spend my time.
That's okay. It's not failure or laziness to choose not to devote my entire self to writing. It's knowing what I need and want in my life. It's understanding the nature of limits and the healthiness of boundaries.