Help my zucchini please!

Hey everyone! I’m pretty new to gardening, been doing it for about 5 months now in south Australia. This is my first zucchini to show up from my plant and have since harvest a nice healthy one, where as this one has stayed looking quite sad.

What do you guys think the best course of action would be? Should I just cut him off?And what caused this?

Thanks to anyone that helps me out! 😊