What are the disadvantages of ERC-20?

Can you elaborate on the drawbacks of ERC-20 tokens? Are there any specific issues with scalability, transaction speed, or compatibility that developers and users should be aware of? Additionally, are there any security concerns or limitations in terms of customization and innovation when utilizing ERC-20 as a standard for token creation? It would be helpful to understand the full picture of the potential disadvantages before deciding on adopting ERC-20 for a particular project.