Hey, Oliver. Thanks for that.
One needs to be careful not to confuse publishing consistently with publishing frequently. If you're publishing one thing per month and stick to it for years, I'd argue you're still being consistent.
Now, whether once per month is too much or too little, depends on what sort of writing you're doing. If you're publishing one book per month, I’d argue that you're being way too ambitious, rushing things, and probably publishing half-baked work all the time. If, on the other hand, you're publishing a five-minute blog post once per month, then yes, you probably need to do a bit more work :)