One of the easiest ways to tell if your butternut squash is bad is to give it a good ol' visual inspection. Check for any soft spots or mushy areas - if it's developing a squishy texture, it's time to say goodbye. You can also look for any slimy or waxy patches, which can be a sign of over-ripeness or even rot.
Imagine you're at the grocery store, and you're browsing through the produce section. You'd probably avoid picking up a bruised or brown apple, right? It's the same with butternut squash - if it looks a bit worse for wear, it's likely not worth eating. And trust me, you don't want to risk food poisoning just to save a few bucks or avoid wasting food.