I hate generalizations like this. If you haven't worked in a restaurant you have no factual basis to make statements like this.
Actually, I do, because we have had MANY, MANY, MANY *EXPERIENCES* with bad service since late 2000. Do you go out to eat 2-3 times a weekend, which we have just about that since late 2000. Think of all the things we have experienced. Wrong entrees-one admitted putting the order in wrong(which also brought it out wrong himself), another admitted grabbing the wrong one from the kitchen), overcharges(all kinds from rung up wrong table on our credit cards 3x's to wrong prices that they could have noticed first by getting their manager to fix it before we had to find the error, to wrong rung up items, to extra items), servers assuming things such as wanting my appetizer with my meal just because we ordered 2 appetizers as well as 2 entrées when I NEVER ONCE said or implied such a thing, to servers being rude, to servers not giving us back our coin change without our permission to keep it, bringing out wrong side dishes or forgetting side dishes, forgetting condiments or wrong amounts of condiments, to getting drinks brought out wrong(dr. pepper was ordered, brought out sprite, like duh color difference), drinks wrongly brought from the bar such as asking for salt on the margarita, then bring it out without salt on the rim, to asking for no pickles(pickles on the plate or on a toothpick on top the bun) brought out by the server themself, servers that admitted putting in the order wrong even though some other server brought out the food, etc. Get what I am saying? We have been through some crap as well as good service as well, but what I am saying is, I have a LOT of room to talk about how it was the SERVER'S FAULT for all these things that happened.
Do servers make mistakes?
of course just like any other profession. But what matters is what they do to correct their mistakes.
What matters is not just what they do to correct the mistake, but if they are trying their very best. A LOT of servers out there are LAZY. Too lazy to compare the written order to the food, then bring you the wrong things that are so obvious to the EYES that the CUSTOMER can see it within 2 seconds of hitting the table. It DOES matter if they make many mistakes. Ever have servers make 5-6 mistakes IN ONE DINING EXPERIENCE? WE SURE HAVE!! That deserves no tip PERIOD, because that server doesn't care about their customers and isn't trying at all. I can accept one, two, small mistakes, but that many(5-6), you aren't trying at all. That's just ridiculous.
Also,Waiters depend on a lot of other restaurant employees to provide a good service. A lot of restaurants have 'food runners' whose jobs is to take the food to the table when it's ready. Sometimes whichever waiter happens to be in the kitchen and not too busy will also take the food to the table. If they don't look at the ticket closely they can take out the wrong sauce to the table. Which will have nothing to do with the waiter who took the order.
I know about this already. Most chain restaurants have no food runners, just other servers running each other's food, meaning no tip outs to the other servers that run the food that isn't their tables, which is WHY service is so bad when another person brings out the food, because there's no incentive to read the ticket by comparing that ticket to the food(assuming the ticket is correct of course).
As far as condiments go, those can ALWAYS, ALWAYS be brought out BEFORE the food is ready REGARDLESS of WHO brings you your food, so missing or wrong condiments that are served on the side that are wrong or missing are 100% the SERVER'S FAULT if they are wrong or forgotten, NOT that other server's fault. The person making the tip is supposed to **EARN** their tip by PREVENTING the mistakes they can from happening. That's why we are paying OUR SERVER and NOT THEM!!
If it's a busy restaurants (i.e., chains), chances are the kitchen staff will not make a separate order of fries just because someone wants them yellow. However, If they are willing to do that, you should be willing to wait a few extra minutes to get your fries.
They do at the chain restaurants I go to(Chili's, Applebee's, and Outback, etc.) Most of the time, I don't have to wait longer honestly unless the kitchen staff messes up.
Also, keep in mind you're not the only customer in the restaurant. If you're very picky and very high maintenance, a waiter will make a decision if he/she wants to spend too much time and energy on you at the expense of the other 4-8 tables that he/she is responsible for.
I know I am not the only customer 99.9% of the time, but we have been a couple of times at certain restaurants at unusual times(not near closing, just unusual times). Then they will get the tip they deserve for not caring about ALL their customers equally. What if all their customers are high maintenance? The server should care about ALL of them EQUALLY SO.
Customers can set the tone for the kind of service they receive. If you treat your waiter as a servant and expect him/her to jump every time you snap your fingers (which btw is a big no no) there is a big chance that you will get less than optimal service and maybe a surprise in your food to boot.
I treat them NICELY. I ask for things NICELY. I say "Thank you" when they bring me things. I am NOT a MEAN PERSON!!
Having said all this, i hold the waiting staff to a high standard for things they can control.
The waitstaff can control most things. If you read my first post, you would see all the things that are listed as far as food goes. They are in control of all overcharges, because they can get a manager to fix a mistake BEFORE they decide to give me the check with an overcharge on it. It's call being caring and non-lazy. There's not too many thing not in their control. There are some things, but most things they CAN VERY MUCH CONTROL before it gets to you wrong.