The plastics used in 3D printing behave differently under a constant tension, some are elastic and return to the original shape when that tension is removed, some creep, and take on a new shape as a result of that strain. Then there’s crazing and cracking which you can see in the print above.
A fine set of cracks initially appear in the plastic, then it finally cracks days, weeks or months later. I find this happens with the plastics that are sold as transparent ABS, even when the tension is relatively light. I do like the appearance of these plastics so I still use them, but I’m careful to avoid using them in situations where I think they’ll break.