1) It sits on the hair
Would you melt candle wax and then put it on your hair? Of course not. But when you retwist your locs with beeswax, a similar process is happening. Beeswax does absolutely nothing for your hair. It cannot moisturize your hair. All it does is solidify on each strand and hold them in place. That may sound like a good thing for retwisting your hair, but it's very bad.
When something coats your hair strand, nothing can penetrate that barrier. That means conditioners won't be able to do their job. The hair also can't "breathe."
Beeswax is about as hard to wash out of locs as candle wax. Even the harshest of detergents wouldn't be able to get all the beeswax out of your locs.

2) It causes build-up
So beeswax sitting on your hair strands in itself is a form a build-up, especially if you're regularly retwisting with it. The real build-up happens when you try to use other products on your locs on top of the beeswax.
The conditioner you tried to apply while washing your hair wasn't all that effective, so now you're trying to keep your hair moisturized during the day. Leave-in conditioners and oils are being put onto your dry, suffocated locs daily and it's still not working. The beeswax is blocking most of the product from working and the rest is just sitting on top of the wax.

3) It causes dehydrated, brittle hair
All of what you've read so far is the recipe for dry, brittle hair. Beeswax makes locs feel extremely stiff. Healthy locs should feel soft and have some movement to them. Because the beeswax is blocking your hair from the moisture that it needs, it's dry, hard, and starting to break.

4) It causes dead-looking "dusty" locs
On top of being dry and hard, your hair also looks dusty. You can see the white to yellow-ish product build-up in your locs. Your hair also looks dull and lacks shine. Healthy locs are vibrant, have bounce to them, and look moisturized. But if you're using beeswax, it can be nearly impossible to achieve that look.

5) It attracts even more dirt and debris
Product build-up in locs attracts more build-up in other forms. Lint, dirt, dust, and other nonsense will be picked up by the beeswax in your hair. All of that stuff will also be hard to wash out of your hair because it has "bonded" with the wax build-up.


Please don't use beeswax to retwist your locs. Instead, opt for a light gel that will wash out easily.
Something interesting to know is that some people don't even use a product to retwist; they just wet their roots and retwist. I actually do that every now and then with my edges.
Retwisting is not so serious that your need the hold of a wax. Stay away from them and your hair will thank you for it.