And even the "third try" rule is the most lenient case for the seller here. Firstly, For mass produced devices (not with BTO models!) you generally have the right to demand a new replacement instead of waiting weeks for the repair. And the "three tries" is actually only an upper limit (and AFAIK only explicitly stated in a few countries) - if you agree to a repair you can demand a reasonable deadline, which trumps any number of tries. So, no, you don't have to accept "repair->2 weeks->failed->another 2 weeks".

(All this under the assumption this happens in the first 6 months, when the law assumes a fault at the time of sale as a default and consumer rights are strongest)