I did some wild ferments few years ago. The main criteria is if it smells and tastes good.
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lactic smell and taste (like yogurt or cheese) is fine but for some too acidic
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alcohol don't smell that strong, it is usually just a hint
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fruity and funky notes are good
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vinegar smell is bad, it means you made vinegar
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bad smell and taste like bitter, chemicals or rotting this can be dangerous, but it's disgusting so you don't drink it
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...
Try it and you will see.