Participate in ICO is risky. many projects are closed. By experience the best time to participate in the summer ICO. It is also better to use insider information

There is no right or wrong time to invest in an ICO, you just have to pick the right project regardless of when you choose to invest.
Most people don't really have insider information, so it's silly to give that as advice.
Instead people should focus on doing research about the team, technical aspects of the ICO and what kind of work has already gone into the project.
You are absolutely right.
Sadly, that is not what is being done.