Last time in 2017, there are many exit scams happening in many projects especially in ETH platform (called tokens) with the "E" token name since the trend of
eBTC project creation. There are too many project plagiarism that copies eBTC (Example: Tokenize version of ETH, BCH, Ripple, Doge etc...) which are many investors getting hype in those project because of the popular coin/token ticker name with it and ended up investing in no value/fake projects. Their livechats usually in Telegram and Slack.
In 2018, there are many reports that a newly created coin/token project almost all info's are plagiarism and putting a team that doesn't involve in the project in the first place (Identities were real but the person isn't even into cryptocurrency) and also running a ICO with a fake data of coin/token purchases (based on explorer) or the coin/token doesn't exists. Now the scammers using a team members that with randomized picture and name! They putting a picture of a team and the name is randomized so the people who'd like to invests to the fake projects can't track on their info's (and some admins/mods in live-chat apps like Discord & Telegram saying that they're real and they already did meetup in some random events about crypto trying hard to convince investors to invest). If scammers can't convince investors, they're running a Airdrop/Bounties that has KYC required (they need your passport most of the time) which they'll sell your identities thru black market.
Now in 2019, there are noticeable exit scams of coin projects with masternode + huge premine by devs (more than 10 projects) in january. They're announcing members especially investors to invest in their pre-sales (which is the bonus is more than 100% of bonus coin/token purchases) which can attract investors and joining into mn. After the coin is listed on the newly or low volume exchange especially the free or vote listing, they'll set their own coin price before they'll announcement of their project is listed on exchange. After having fake high volume (which the devs buy and sell their own project currency) in 3-5 days, they'll getting lists on CoinMarketCap and more members will hype about the project price is almost the same as the pre-sales. Investors especially the whale will bite the price and pump it higher and higher, in that time, devs will sell their huge premine and abandoning the project like they didn't make a project at all. They're mostly in Discord now. Be careful of some random folks which is dming you with their discord invitation link in their first posts. If you're a investor and unsure what altcoin will you invest, invest and hodl BTC and ETH instead.
Take note: This is only my experience and opinions, I might be wrong in some point of what I post.