No problem at all. So everything is trying to complete a circuit. The main hot and grounds are coming from the battery. The main battery ground needs to go out and connect to the engine block (which bolts to the transmission, starter, etc), the body, and the chassis. The hot side of the battery goes out and connects to the starter, charging system, fuse panel (the fuse panel is then further divided up into switch wiring)... so let’s take the ignition switch. It has a main constant battery hot coming into it (power in) and when you turn the key all your doing it sending power from that power in—through the switch and out to different wires. To the fuse panel (to feed rows of fuses) to the coil, and to the starting system. The only reason for power to come out of the switch and through these wires is that it has a path to ground. So if you take the starting system: when you turn the key to start, you’re opening up a pathway to the starter (which is grounded to the engine block) so that power comes out of the switch runs into the starter solenoid (which is just a relay to help with all that amp load drawn by the starter) when it gets to the solenoid it closes a set of contacts (hot and ground) and then allows power to flow from the battery to the starter to spin over the engine So everything needs a complete circuit to operate properly. Without a path back to your battery ground, there is no power present. If you connect a piece of wire to your battery positive, there actually is no power in that wire, until It has a path to ground (the same battery ground the power is coming from) In the case of adding a push button start, all you’re doing is adding another switch (like a valve) to control the flow of electricity. So everything still acts the same way, the power still tries to find it’s ground at the starter solenoid, but it can’t go past the push button until you press it an give it the pathway to the ground. That’s why grounds can cause so many weird problems. It doesn’t really know where to go, it’s just trying to complete the circuit (find ground). So if you took a piece of wire, connected it to a battery positive, split it and ran one wire to a bulb in front of the car and one to a bulb in the rear... powered it all up...if the ground in the front was better, the front might only light up, or the front might be brighter and the rear more dim (depending on how much ground the rear bulb was getting). It can do weird things trying to get to where it wants to go. Sorry for the lengthy explanation. I could do this all day...and I do!