The exchange another person uses may not be the exchange that you should use. What is "the right one" for you is not necessarily the right one for me. This is a very good question! Yes, it matters. And this is how you pick one. You need to answer the following questions:
Is it important for you that your exchange accepts deposits of cryptocurrencies? (Yes/No)
If you currently have cryptocurrencies and just want to change your exchange, the new exchange must accept deposits of cryptocurrencies. Some exchanges only do Fiat-to-crypto and those exchanges are then not available to you.
Is it important for you that your exchange accepts credit card deposits? (Yes/No)
I would personally steer clear of buying cryptos with credit cards but if you want to do that, all exchanges do not offer that option.
Are you a US-based investor? (Yes/No)
Many exchanges prohibit US-investors.
What’s the highest fee you can accept to be charged?
Trading fees range from 0 to 20.00% (yeah you read that right, 20.00%). The lower fee you require, the fewer exchanges are available to you. Industry average is arguably around 0.25%.
Which cryptocurrencies do you want to trade?
A very important question of course. If you’re looking to buy BTC and ETH, most exchanges have that option. If you’re looking for a less known coin, not all exchanges will have that.
The above questions (+1 more regarding continent of exchange) are included in our Exchange Finder tool! You just answer 6 questions and then you get matched with the exchanges that fit your answers. Here is the link to the test: https://www.cryptowisser.com/
Good luck!