It depends on your launch goals and size of your audience.
If your goal is to get the badge and you have a less audience, it is better to launch on weekends.
But if you goal is to get traffic and you have bigger audience, you can launch on Wednesday, and Thursday.
The competition is higher than weekends and a bit less than Wednesday and Thursday. So, if you have decent number of audiences, you can launch on Tuesdays.
I've been told by a number of sources that it's Tuesday-Thursday as people have settled in the work week and will pay more attention if you wish to drive eye-balls. However, other days there is less competition so that you are more likely to rank higher if you are shooting for social clout.
When deciding on the best day to launch your product on Product Hunt, think about the people you want to reach.
If your product is meant for businesses and professionals, it makes sense to launch it on a regular workday when these individuals are actively searching for new tools or solutions.
On the other hand, if your product is geared towards consumers, you might want to pick a day when your potential users are more likely to be casually browsing Product Hunt.
Thursday is a great day and I have come up with my logical explanation. :) Almost 80% of folks are chilling on Saturdays and Sundays, and nobody wants to deal with work drama on Fridays. But we gotta wrap up the week, right? That too conclusive and productive. So, Thursday is the sweet spot to figure out what we need. Plus, launching a product on Thursday, it's like hitting the jackpot – more people show up, and there's a buzz in the air because it messes with people's minds in a good way.
We launched the BoldDesk on Monday and ended up in 5th position. Got the 100+ new signup from the product hunt.
It's depends on your product audience and target for your campaign
There's no universal "best" day to launch a product; it depends on your target audience and industry. Consider weekdays for B2B, and weekdays or weekends for B2C, avoiding major holidays or industry-specific busy periods. Test and analyze to find the optimal day for your audience.