Bounce rate is the percentage of sessions that end without a second action - no other page viewed, no event triggered. A high bounce rate can signal a mismatch between what people expected and what the page delivered, or a slow, confusing, or unconvincing page.
It needs context, though: a blog post that answers a question completely may have a high bounce rate and still be doing its job. Treat it as a prompt to investigate, not a verdict on its own.
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