If you inject into your body, and it does not leak out, it's not wasted. It's in your body. Absorbtion will be variable, but it's IN YOU. Even leakage into the subq area will eventually absorb.
The downside is the nerve/blood vessel in that area..
My nurses that give me test shots in the ass are morons.. they are usually really high/outside or low and center (near the are you described).
No bad experiences yet...