What is the most important during the launch?

I have checked more than 20 different articles and the main thing I noticed - is plain voting every timezone, every hour.

I'd say all of these (upvotes, comments, hour) are important. But the most crucial part is your product and content... I saw a top product with just a simple idea but it has a good CTA, video, and images. And I saw a top product with just simple images and CTA but with great idea & landing page

A product launch serves many purposes for an organization— giving customers the chance to buy the new product is only one of them. It also helps an organization build anticipation for the product, gather valuable feedback from early users, and create momentum and industry recognition for the company. PrepaidGiftBalance

I have observed that a product that gets more upvotes in the early few hours of the launch mostly makes it to the Number 1 Product. So I would say Upvotes and times both matter.

In my opinion, the most important things in the success of the launch are quality of the product and team cohesion. In this way you will take a decent position:)