Why does a motorcycle start with a clutch or neutral position?

When starting a motorcycle, one thing to consider is the load issue. If starting with wheels, the resistance will increase, which can cause damage to the starting motor and gears. Another and more important aspect is safety. If the engine and wheels are connected together, that is, when starting, the engine will directly drive the wheels to rotate, causing the entire vehicle to move forward. When the internal combustion engine starts, it is explosive, and the vehicle will naturally move forward sharply. Therefore, some car manufacturers only allow you to land in neutral or clutch mode when designing cars, which is a safety design consideration
You can start in neutral now, so the starting system is normal. Other gears cannot be started. It should have added a gear switch interlocking function during the design, and may also have added a clutch switch interlocking function. Some cars also have brake switch and other signals locked in, which means that only in neutral position, there is a normally closed switch output to the starting relay circuit, In other gears, a normally open point is output to the start relay circuit. This way, you can only start by pressing the neutral gear, but it is estimated that the foot start is not controlled.
Similarly, when the clutch switch is pinched, it will output a normally closed point to the starting circuit, while when the clutch is released, it will output a normally open point to the starting circuit, which is interlocked through the switch. As for what you said, sometimes it works, sometimes it doesn't. It's probably caused by poor contact of this interlocking switch. You can disassemble it to adjust its position, or replace it to solve the problem.
For a regular range rider, it is best to press the clutch again during startup, regardless of whether it is in neutral or not. This can reduce the resistance of the starting motor and extend the lifespan of the starting system. For a horizontal cylinder engine, it uses a clutch plate to transmit the power connection between the starting shaft and the crankshaft. If you hold the clutch, this connection will be disconnected. If you hold the clutch, you cannot start it with your feet. Of course, electric starting is not a problem.