For me, ICO, IEO and IDO are all ways for new projects to sell their tokens, they differ only in safety and where they do it. Profits from investing in a new project depend on the project itself, not the token sale.
1. In 2017-2018, ICOs were very popular, hundreds of projects launched their own token sales: they received crypto from investors (BTC, ETH) and sent tokens to investor's address. This event is not guaranteed by anyone so risk is very high, many projects are actually just a way for scammers to make money.
2. 2020-2022: CEXs have become bigger, new projects have come and opened token sales, we have letter E = Exchange in IEO. Project information (team, solution, tokenomics) is audited by CEX's team of experts. IEOs on Binance Launchpad have been very successful.
3. At the same time, many decentralized Launchpad platforms were also born, and we have letter D in IDO. The most prominent is CoinList. For me, IDO is less safe than IEO because Launchpads can make a mistake and list the IDO of a poor quality project.