Today's depressurisation incident might have been caused by unscrupulous construction workers. Noteworthy, the pipes were laid by the ship Akademik Cherskiy, positioned with low accuracy (using anchors) — this led to errors in laying and joining of "coils". Most likely, it was the reason for the relaying of one section, perhaps the one that was depressurised today.
Apart from failure, it might be deliberate self-liquidation of the project. There are several motives.
Probably the most important is the payment of insurance for the incident and the use of these funds to repay the loan extended for the implementation of this project and financing of "transparent" supply by companies close to the Kremlin tyrant.
The second motive is to exert pressure on the sanctions policy by demonstrating the need to preserve environmental and technical safety in the Baltic region.
The third motive is to further heat up spot prices at German gas hubs.
In general, it was quite surprising that depressurisation took place on the eve of Baltic Pipe commissioning.
https://razumkov.org.ua/komentari/pro-intsydent-na-ns2-brak-chy-svidoma-samolikvidatsiia