As someone who has worked in aerospace, and is also familiar with the saga of Boeing:

Boeing bought McDonnell in the mid 90s, but the McDD leadership essentially was able to work the situation such that they got inserted as the leadership and management of the now-merged company. They then proceeded to focus heavily on financial matters and stock price, with extremely predictable results.

To wit: there was actually a brand new plane in the works to replace the 737, but it was killed because leadership wanted to wring every possible penny out of the 737 design, despite the fact that the platform had reached its limits in several important and meaningful metrics. One of those metrics is “modern efficient engines can’t fit under the wings anymore”, which led to the (now obviously) ill-advised nacelle redesign and subsequent CG changes that necessitated MCAS if they wanted to maintain pilot type ratings without a new training/rating program (because those are expensive)… and then they made redundant safety features around that whole thing optional add-ons. For this door snafu, it was a matter of outsourcing work and then never doing the absolutely required work of fully integrating QC process and systems between the contractor and Boeing.

There are of course many more projects and issues within those projects - the 737 is just one of the most glaring current focuses (as in: the defects are CLEARLY design and manufacturing process defects).

Boeing has a disturbingly clear record of prioritizing profit over safety repeatedly in the last few decades. Things are just coming to a head now, because the lack of safety-oriented culture has truly come home to roost.

If you’re talking about the 757 that lost a nose wheel recently: it’s still under investigation, but at this point I think it will likely be chalked up to a one-off maintenance miss