This post is an elaborate and long one. I always try to make a TL;DR for all posts I make but I request you to read all of this one.

Because,

We never know how, why and when our future self might get the best out of us.

In crypto sphere, be your own bank and easy trading is a double edged sword. There's no customer care or blocking spending cards/wallets and other support. Which makes it a good target for any kind of attackers. With all kinds of malicious things happening to holders, I'd like to make a list here.

I would categorise these into 3 types. Greed, Hacks and Stupidity.

1. Greed

This is a consequence of human mentality and FOMO. I believe greed results in more scams than others. Types of greed scams are...

1. Giveaways : These are events where a scammer asks you to send him some amount of crypto and says they will send back double or more. It's never coming to you, never ever believe these promises even if the sender/attacker is seemingly legit or even Elon Musk lol.
2. Ponzi Schemes : These are detectable in crypto space by abnormal APY(interest) rates. They offer you staking rewards abnormally higher than rivals and market standards. They also offer you levels and tiers and bonuses if your referrals get in too. Never trust these..If you wanna go down the rabbit hole, look up Bitconnect.
3. Pump and Dump : Pump and dump is a situation where a group of early buyers try to get in more newbies and then try to drive the price up. They often create these so called "VIP" groups and invite people as if they're lucky. Once the price reached their target(it pumped), they exit sell huge bags(dump) at the cost of newcomer's money.

2. Hacks

These are result of some clever people putting their skills at work of stealing/scamming your crypto.

1. Fake Wallets : There are often crypto wallets with unbelievable similarity to original ones. They also have bots commenting it's very good and also decent upvotes on app stores. Once you install them and deposit your crypto/enter your seed then consider the crypto gone. They will instantly suck up your crypto to their wallets and you can do nothing but report the app. Solution :  Look for legit developer names and app rankings or visit the legit website directly to download the wallet. For geeks, verify the checksum if available.
2. Address Malware : These are often programs that are injected into your computer when you visit/download some free software or play those free games. What they do is download a program onto your computer. When you copy your deposit address from somewhere like an exchange, the malware overwrites your clipboard with the hacker's crypto address.  When you paste the address on the send address, you are sending it to a hacker.Solution : Double or Triple check the address you pasted before clicking send.
3. Phishing Scams : These are hacks where a malicious website or URL shows up in your chat or emails. Which might look legit but isn't. Hackers take advantage of unicode characters and set up websites whose URL is same as the original and the UI of the website will be same too. Once you try to login and enter your credentials, hackers will take those credentials and log in to your account and can steal your funds or even worse, transfer tainted BTC to your wallet and sell. Solution : Check URL security and if possible, certificates. Use 2FA, preferably an app rather than an SMS 2FA(In case of sim swaps).

3. Stupidity

These are a result of pure stupidity or incompetence from the holder's side.

1. Seed storage methods :  Almost all of wallets when displaying seed ask the holder to write their seed and chuck it away at some safe place. But, people being stupid, store it as a screenshot or save it as an email draft or in cloud/something in a digital form. This is a huge compromise and you may lose your crypto if you risk to do this. All the glory of "Crypto" in cryptocurrency is lost if you as a holder don't make the effort to safeguard your wallets or finances. Solution : Write it down in physical form in copies, laminate the paper, store those at individual trusted places safely and if your funds are huge, then get a safe.
2. Not using 2FA : 2FA these days is almost becoming the norm as email verification was 5/10 years ago. By not using 2FA you are just a sitting duck waiting for some hacker to get your credentials and login. It is as simple as scanning a barcode in an app. Make it your priority.Solution : Please enable 2FA and preferably an app based as SMS based are vulnerable to SIM Swap.
3. Revealing your holdings : We all can admit that sometimes we are excited by our gains and want to flex them over our friends and have a " Told you so" moment. It isn't worth it. However trustworthy your friend might be, the people he shares the news with might not be so trustworthy. It is always better to assume the worse and every person has a 0 they fall at. Some fall at 1000$ and some at 10,000$. Your gains might become a potential target for the greedy. Solution : Never reveal your crypto to anyone, if you already did then go for boating today.

That's it people, I think I mentioned all the general scams. If anyone thinks I missed another prominent one, I'd be glad to edit and include here.