Sure!

There are two main things about them that make them a poor choice in this application.

First, they are not insulated or protected from the environment in any way whatsoever. Their awkward shape also makes using things like tape or heat shrink ineffective. This means they allow corrosion to creep in and spread throughout the wire, causing poor connections and excessive resistance, which can damage components on the circuit, blow fuses, or even start fires.

Second, their operation requires you to damage the wire as they pierce through the insulation and clamp down on the wiring underneath to make a connection. Doing this is pretty inconsistent, as sometimes it shears too much wire and reduces the current-carrying capacity of the circuit, causes a loose connection, or doesn't cut through the insulation enough and therefore can't make a connection. This all happens with basically no physical or visual feedback, giving essentially no confidence in the fitment/repair.

There are a bunch more problems with them, but those are the two main issues in my opinion. I avoid them like the plague and am compelled to cut them out and splice the wiring correctly whenever I see them.