Is a programmer obliged to give a 100% working product without jambs?

Question

Work organization

Suppose a client orders an online store, a landing page, a service, a parser or just a program from us, it doesn’t matter.
Does the client always have the right to demand a 100% working product without bugs and jambs?
What I mean?
Let's say you ordered an adaptive landing page, and under some browser on some device, the text moves out at a certain angle.
It is clear that checking under all devices that everything is displayed is hard and long, it takes a lot of time.
Or let's say you ordered a site parser, you checked everything is OK, but in very rare cases there is some kind of non-standard layout on the site that you did not notice during development, and the data diverges a little.
These are all 100% programmer mistakes, and will they need to be fixed for free?
Or is it a natural part of development, and subsequent edits should be done only for money?
I understand that there are contracts, but you will not take into account all the subtleties in them
. Have you ever had such situations? How did they do it? Or did everything always go smoothly?

Answer 1

To do this, there is a clause in the contract about Product Support (during a certain period of time) after its delivery to the customer.

Answer 2

one.

Let's say you ordered an adaptive landing page, and under some browser on some device, the text moves out at a certain angle.
It is clear that checking under all devices that everything is displayed is hard and long, it takes a lot of time.

A list of browsers / devices is compiled in advance to check the correctness of the display, according to the design layout. If not listed, it is checked under the top 5 (IE, FF, Chrome, Opera, Safari) advanced/leading browsers for desktop and mobile systems.
2.

Or let's say you ordered a site parser, you checked everything is OK, but in very rare cases there is some kind of non-standard layout on the site that you did not notice during development, and the data diverges a little.

This is the "cant" of the performer, 100%. He should fix/modify for free.
3.

These are all 100% programmer mistakes, and will they need to be fixed for free?
Or is it a natural part of development, and subsequent edits should be done only for money?
I understand that there are contracts, but you will not take into account all the subtleties in them.

Everything that is written in the contract must be fulfilled. The expected quality of work - you can always fully prescribe it too. If something is missing in the requirements, the contractor has the right not to do this, if this does not entail a violation of the contract on his part in any of the paragraphs.
PS: In general, it’s better not to do this on his part, because. it is his reputation.

Answer 3

Not necessarily, you can do your job through the ass, and the more bad programmers who make low-quality projects \ products \ code, the less competition and good programmers.

Answer 4

I agree with xmoonlight.
One of the first postulates of testing: there are always errors. When you draw up a contract, you must have a technical task written in the application. For an example with a site, you can specify permissions and supported browsers, technologies on which you write.
In this case, you can arrange improvements and corrections of errors with the customer for an additional fee.