Yeah that's a good point. KMC chains aren't designed to be joined, you should be using the split link which is shit. When you're joining the chain, the pin should go through the hole fairly easily. If you force it, you'll bend the outer plate which will compromise the strength of the chain so look closely while you're joining it. If you force it really hard, small cracks will appear around the hole. There's a neat way of avoiding this, once you start feeling resistance, take the chain off the tool and loosen the link by waggling it around. Reinsert and repeat if needed. Works most of the time.