It as a dark color and it emits a bad order that is easily recognizable
You know when french onion dip has gone bad because it has water on the top.
To determine if your frozen salmon filet has gone bad, check for any off-putting odors, discoloration, or changes in texture, such as a slimy surface. If the fish appears freezer-burned, with dry spots or a grayish hue, it's best to discard it. Additionally, if the salmon has been stored for an extended period beyond its recommended freezer life (typically 3-6 months), it's safer to err on the side of caution. Always trust your senses and when in doubt, throw it out.
when it does not work
you know when you are not cotrolling the car.
check it
If you eat it and then throw up. ;)
If it is stale and a very light brown and nothing grows on top of it, then you know you have bad soil.
The steak may go bad and leave a bad odor.
It will probably smell bad or have a noticeably weird flavour to it.
Swap it with one you know is good.
Well it all depends if the sound of the engine is abnormal or muffled then it prolly gone bad and if it dont start then well you know its bad
Try smelling it if you still dont know, pour some into a glass and see if it looks clumpy or thick. Dont drink after its gone bad!