but i see that have some telegram channel that provide free signal, we know that Profit and Loss both have in trading.
Just assume that I create a channel on telegram and spam its name all over the internet in order to get a large following and then just post whatever coins I have in order to allow the members to pump it so I can dump on them - does that not sound like nice method to "scam" these people? Afterwards just delete the group and your account and everything is gone, with nobody to pursue you for any legal actions.
In today's internet, where anyone can become anything without qualifications, we have numerous "Life-coaches" and "Financial Advisors" who are none but manipulative people who know there is a market for people to guide gullible newbies into traps.
For this reason after joining in any signal group, need to analyze their previous signal or present signal, just see that really their signal is helpful or not then people can start their work.
That is a good idea, but would you rather not spend time preparing your own charts than on this? Besides the number of channels that actually post something logical is <1% and they are not easy to find. Noise is much more than Signal here and that also indicates how easy it is to run these pump and dumps.