When a new restaurant opens, there are a number of people who rush there and soon after post their thoughts and reviews. There is certainly nothing wrong with that and I engage in such behavior sometimes as well. Plenty of readers want immediate knowledge about a new restaurant.
But this comes with a caveat. Anyone reviewing a new restaurant must take into consideration the fact that it is new, and thus needs some time to work out all of the kinks. You cannot expect perfection from the start. It generally takes 2-3 months before a restaurant has worked out its issues. Menus may need to be revised, servers may need additional training, the food may need some refinement.
Unfortunately, some reviewers fail to understand this vital point. They write overly negative reviews, without giving any leeway to the new restaurant. They seem to expect perfection from the start, and that expectation is unwarranted and unjustified. Readers should also keep this in mind when reading any review of a new restaurant.
It would be beneficial to conduct follow-up reviews of new restaurants, to monitor their progress, to see how they have changed, if at all. Hopefully you will see positive changes, a correction of any prior issues. After three months, hopefully there will not be any more issues. If issues still exist, then that is a sign of something seriously wrong with the restaurant. Those 90 days should be sufficient to resolve any problems due to their newness.
And if you are at a new restaurant, and detect a problem, please inform the management about it. They will want to know about any issues so they can rectify them as soon as possible. If the management is unaware of a problem, they can't do anything to fix it.
Don't rush to judge a new restaurant. Understand the complexities of operating such a new endeavor and give them some leeway.