A comment is not removed for selling something. It is removed for adding nothing to the thread. The moderator is protecting the discussion under a post, not the market, and the judgement takes seconds.
Removed almost always
- Links. In most channels a link in a comment is deleted on sight, frequently by a bot. There should be no link at all — the route to you is the profile: what to put in a profile.
- Invitations. "Subscribe", "DM me", "we have" — gone immediately.
- Content-free approval. "Great post", emoji. Not forbidden, but useless: nobody taps the name of a person who wrote "thanks".
- Off-topic argument. Politics, personal remarks — the fastest way to be banned from the channel rather than just edited out.
Removed sometimes
Very long comments. Ten paragraphs under a short post reads as an attempt to redirect attention.
Too much of your own experience. The line is thin: "we did this and ran into that" reads fine, a list of your services does not.
Recognisable phrasing. A moderator who sees the same construction from several different people understands the scheme and clears all of them.
The test that predicts it
Remove your comment from the thread mentally. Does anything get lost? If not, it was filler, and it will be treated as filler.
Being early is not enough
A fast irrelevant comment is worse than a slow useful one: it gets deleted and the account is remembered. Speed matters only once the content is right — being first in a thread.
A different problem
Deletion by a moderator and a restriction from Telegram are separate events with separate causes — see commenting without getting banned.
How Neurogram does this
Everything above is manual work that runs into the number of hours in a day. Neurogram does it on your own accounts and without you: it collects channels and audiences, writes comments and replies with a language model, and keeps limits and quiet hours so the accounts survive. See pricing or look at your case.