Inspector General Unimpressed with Boeing's QC, Conformity, Workforce
NASA's Office of Inspector General published a report looking into the use of Boeing's Space Launch System, and recommended that the company be given "diligent oversight to ensure the contractor delivers a quality space flight system."

The program in question largely revolves around a new element that will be added to the SLS Block 1B, the backbone of Artemis IV. In September 2028, the SLS will be used to lift the Orion Multi-Purpose Crew Vehicle capsule along with the International Habitation Module into lunar orbit...or so NASA plans. That launch will begin lunar orbit operations once it links up with the Gateway Station and Human Landing System in order to send astronauts from lunar orbit to the Moon’s surface and back again. Central to that greater mission is an improvement in the form of the Exploration Upper Stage, a new upper section for the SLS. The EUS will give the basic SLS a "40 percent upgrade in capability to send Orion and large cargos to the Moon, from 27 metric tons under Block 1— the SLS rocket’s first iteration—to 38 metric tons for the new Block 1B system." The Office notes that successful rollout and deployment of the EUS probably requires stringent attention and management from outside
Boeing's own, given their lackluster track record in recent years.

Specifically, a review of reports generated from Boeing's previous noncomformances during quality control and inspections led the Office to say that "Boeing's quality management system for Core Stage production at Michoud does not meet industry standards." Instances of sub-par procedure included "contamination of metal shavings, teflon, and other debris" inside the SLS Core Stage 2 liquid hydrogen fuel tank. Other reports found middling bureaucratic cleanliness, with outdated paperwork, administrative errors remaining uncorrected, and a lack of information retention to help trace the source of problems later.
The Office of Inspector General also reported that "Boeing’s Michoud Workforce Lacks Sufficient Aerospace Production Experience, Training, and Instruction." The company had said it was "difficult to attract and retain a contractor workforce with aerospace manufacturing experience in part due to Michoud’s geographical location in New Orleans, Louisiana, and lower employee compensation relative to other aerospace competitors." Boeing assured NASA staff that it provides the training needed to 'mitigate the challenges associated with an inexperienced workforce', but inspectors still found that things would slip through the cracks.

One case came when NASA found QC issues with the SLS Core Stage 3 liquid oxygen fuel tank dome, citing "the dome was segregated and pending disposition due to welds that did not meet NASA specifications." That unit is now being evaluated to "determine whether and how it can be safely used going forward."
There's much, much more to the report, too, as the Office cites the expanding costs and lack of accountability in elements of previous projects. In the end, they recommend that NASA coordinate with Boeing to "develop a quality management system training program, and institute financial penalties for Boeing’s noncompliance with quality control standards. Furthermore, they say, NASA should perform a detailed cost overrun analysis on Boeing's stages for EUS development.