As steering leaks are normally obvious at full lock, I am assuming your question concerns fluid going missing with no obvious reason? A ruptured suspension sphere diaphragm would be a likely way to loose fluid without pools forming on the floor as the hydraulic reservoir feeds more than the steering.
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As steering leaks are normally obvious at full lock, I am assuming your question concerns fluid going missing with no obvious reason? A ruptured suspension sphere diaphragm would be a likely way to loose fluid without pools forming on the floor as the hydraulic reservoir feeds more than the steering.