I think the key is that Sauron never thought that somebody would destroy the Ring. Even more than that, when one is making something they are not usually thinking too much about the consequences if the thing is destroyed. I believe that this is something that did not even enter into Sauron’s thinking until the Last Alliance.
I also happen to belong to the school of thought that says Sauron did not entirely understand all the possibilities of the Ring. He knew what he wanted it to do and what it did. However, this does not mean that he understood all the possible consequences of his actions.
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the phantom should be appearing in this thread shortly.
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So, my answer to your question is that he did not even think of that at all.