Last spring I tried to move some USDT from an exchange to my own wallet. Not a big amount, but not nothing either. I copied the address, pasted it, hit send, and went to make tea.
When I came back, nothing had arrived. I gave it a while. Still nothing. I refreshed the wallet, closed the app, opened it again, like that ever helps.
It turned out the exchange had picked a different network from the one my wallet was expecting. Same coin, same-looking address, different chain. I honestly didn't know that was a thing. Nobody had mentioned it, and the exchange just quietly chose for me.
The money wasn't gone, exactly. It was sitting somewhere I couldn't easily reach, and I spent most of a weekend reading old forum threads late at night, half convinced I'd just thrown away a chunk of my savings. Eventually a support agent walked me through getting it back, and I paid a recovery fee that stung way more than it should have. A big slice of what I'd sent, gone just like that.
What bugs me is how avoidable it was. Every beginner guide I'd read started with "what is Bitcoin" and "what is a blockchain," then jumped straight to charts and price talk. Not one of them said: before you send anything real, send a tiny test amount and wait for it to land.
So that's my habit now. A tiny test, every time, even when it feels silly. Especially when it feels silly. I also check the network name on both sides, not just the coin. If the exchange says one thing and my wallet says another, I stop and sort it out before touching anything.
It's not exciting advice. Nobody will screenshot it and post it with rocket emojis. But I'd take boring and safe over a clever trade any day, and I say that as someone who has been burned by both.
If you're just starting out, send the test amount. That's really all I wanted to say.