So true, and I plead guilty to doing so in the past: Deleting...
My reasoning was, if I posted something about a physician or something that could lead folks to recognizing themselves in what I noted (even without citing their names), I considered the effects on others. I didn't want what I was stating - within the context of "support forums" - to have a possible adverse effect on the treatment I'd receive from physicians and others. I waited (some time - generally weeks to months and when my posts were far off the main pages) and deleted.
At times, I also did so for retaining privacy, since seach engines tend to cache so much personal data that I may not want trailing me for the rest of my existence.
I thought, if the purpose is peer support, I don't want to hurt myself or my care in the process of also seeking support and insights from others

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I know I've not deleted for the purpose of altering the context or flow of a discussion, though.
It was the possible impact of how my words might be used to hurt (not help) me.
I do tend to think about what I've written before hitting the "post" button, but... there are still those times that I prefer not to have a life-long reminder of things that may be particularly painful.
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".... This world wasn't built for people in wheelchairs ...."
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