Red Black Tree clarification I am quite new to Red-Black trees, and therefore I am having a bit of difficult time trying to understand them.

One of the properties of the Red-Black tree is that every red vertex must have two black children, meaning one cannot have two consecutive red vertices.

Can someone explain to me why this is an essential property? What are the benefits of having such a property?
If you check the proof height-balancedness of red-black trees, you'll see that we essentially analyse the black-height $h_b$ of the tree which, by another important invariant, is the number of black nodes from the root to any leaf.

The property you cite then gives us the right half of

$\qquad\displaystyle h_b(T) \leq h(T) \leq 2h_b(T)$,

which allows us to carry over bounds on black-height to usual height.