Can someone please explain to me why (some of) the following macros behave differently?

macro_rules! maybe_skip {
    ($prim:ty, $text:literal) => {
        maybe_skip!($prim);
    };

    (u64) => {
        println!("Skipping u64");
    };

    ($prim:ty) => {
        println!("Not skipping {}", stringify!($prim));
    };
}

macro_rules! maybe_skip_again {
    ($prim:ident, $text:literal) => {
        maybe_skip_again!($prim);
    };

    (u64) => {
        println!("Skipping u64");
    };

    ($prim:ident) => {
        println!("Not skipping {}", stringify!($prim));
    };
}

macro_rules! maybe_skip_again_again {
    ($prim:ident, $text:literal) => {
        maybe_skip_again_again!($prim);
    };

    (u64) => {
        println!("Skipping u64");
    };

    ($prim:ty) => {
        println!("Not skipping {}", stringify!($prim));
    };
}

fn main() {
    maybe_skip!(u32, "bla");
    maybe_skip!(u64, "bla");

    maybe_skip_again!(u32, "bla");
    maybe_skip_again!(u64, "bla");

    maybe_skip_again_again!(u32, "bla");
    maybe_skip_again_again!(u64, "bla");
}

Output is:

Not skipping u32
Not skipping u64
Not skipping u32
Skipping u64
Not skipping u32
Skipping u64

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