Guys, do you have any suggestion about how one exchange can gain trust into traders. It will be appreciated!
And do you know any crypto communities for Ethereum, exchanges, blockchain where I can talk more about our decentralized platform
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https://weidex.market/ 
I think that trust is earned over time, and that confidence is ranked in Coinmarketcap because most experts look for the page to see the top, if you are not there, you will hardly have confidence in the traders.
You can search for many communities that you can pay to get good publicity with a lot of traffic and an excellent marketing team, but one of the things you can never neglect is the support team.
Today many traders complain a lot because support is not fast, also an important issue to take into account is that you must be very careful with security, you can not allow being hacked.
There are many Level 1 Exchanges, which handle large amounts in terms of money, to win the trust of the traders, you must attract the whales that are causing the necessary chaos, and with this, you must be very Pending arbitration, do not leave or neglect because you can be fined or prohibited.