Always. I am spending a lot of time by reading the whitepaper, investigating the team members, checking the communities in social media. But the most important aspect of any research is an MVP or a working product.
Yeah, even if there is only a small amount of money involved, only a fool would invest in an ICO without the simplest idea about that project. I think doing an initial research about the project is the right thing to do first since it would more likely guide a prospective investor on deciding whether to invest or not. And as a rule of thumb, investors must first have a due diligence first on that project to avoid substantial losses that maybe incurred if they chose not to do it voluntarily.