It may be rewritten but it is an entirely new product. The new code does not replace old code. The old code continues to live and run on/with the older product. This reduces risk of breaking things but also increases costs due to running multiple versions. It's all trade-offs.
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Not sure where I heard it (probably some podcast), but Basecamp is rewritten every few years from scratch.
It may be rewritten but it is an entirely new product. The new code does not replace old code. The old code continues to live and run on/with the older product. This reduces risk of breaking things but also increases costs due to running multiple versions. It's all trade-offs.