Most consumers lose a warranty argument because they believe they must prove the product was already broken. In the first year it is the other way round.
If a defect appears within one year of delivery, the goods are presumed not to have conformed to the contract at the time of delivery. The seller must then demonstrate otherwise. If it cannot, the defect is treated in law as having been present from the start.
Article 7:18a(2) of the Dutch Civil Code: in a consumer sale the goods are presumed not to have conformed to the contract at delivery if the deviation from what was agreed appears within one year of delivery, unless the seller demonstrates otherwise or the nature of the goods or of the deviation precludes it.
This is not a warranty period and not a right that lapses after a year. It is a rule of evidence. After that year you hold exactly the same claim under article 7:17; you simply have to make it plausible yourself that the defect was already there.
Without this rule, a consumer whose phone stops charging after four months would have to show that something was already wrong at delivery. They cannot, and the seller knows it. With this rule, the seller has to show that the defect arose from something that happened after delivery: a drop, water, misuse.
The standard response of "this is user damage" is therefore not a conclusion but an assertion the seller has to substantiate. A report from a repairer engaged by the seller itself, containing no more than a ticked box, is not that.
The nature of the goods. For products with a limited lifespan the presumption sits differently. A set of batteries or a pair of cheap earbuds cannot be expected to last a year.
The nature of the deviation. For damage that by its nature comes from outside, such as a cracked screen or water damage, the defect precludes the presumption. That does not mean the case is hopeless: a screen that cracks spontaneously without a drop is still a manufacturing fault, and it then turns on who makes what plausible.
A manufacturer's warranty is a commercial undertaking alongside the law. It can supplement the statutory claim but never limit it. Article 7:6(1) prohibits departure to the buyer's detriment. A seller saying "the warranty has expired, there is nothing we can do" is relying on its own undertaking and ignoring the statutory conformity requirement, which simply continues.
How long it continues depends on what you could reasonably expect. For an eight-hundred-euro washing machine that is considerably longer than for a two-hundred-euro one. No period is set in the statute, and that is a feature rather than a defect.
Under article 7:21(1) you can demand delivery of what is missing, repair or replacement. That performance is free of charge: paragraph 2 provides that the costs cannot be charged to the buyer and paragraph 7 that the seller takes the goods back at its own expense. If the seller does not perform within a reasonable time after a written demand, paragraph 6 entitles you to have the repair done by a third party and recover the costs from the seller.
Then the burden of proof lies with the seller and not with you. Submit the case and we will hold them to it.