it depends on how you look at the events.
If you assume that the assassination attempt was something that happened by coincidence, then it is indeed unbelievable that so many things went wrong and aligned such that the attack could happen, but if you assume that the attack was carefully orchestrated, then it all starts to make sense and the holes in the Swiss cheese model line up to enable the attack:
with all the evidence we have now, it is quite obvious that the holes of at least a 17 layered cheese model were aligned to make it happen (in random order and shooting from the hip) and to make it hard to prove what happened:
- communication issues between various services, including secret services and local forces: no shared walkie-talkies, no shared channels, every service operated in their own silo…
- “not finding” crooks, even though the area is not that extended and there are many recorded sightings…
- not pulling Trump off the stage
- careful selection of the rally venue that made it extremely hard to secure a security perimeter
- the law enforcement officers on the ground turning a blind eye when people shouted at crooks
- insufficiently trained body “guards” who had no idea what to do
- DEI hires
- not securing the different locations of the crime scene
- cleaning up the different locations with critical evidence
- immediate claims of a “lone wolf” that turn out to be false later on
- live media coverage on site by channels that usually do not cover Trump’s events
- even though there were hundreds/thousands of cameras around, uninterrupted recordings of well before until well after the crucial events have not been made available!
- the chain of custody of the audio/video recordings that have been made available is questionable for those that do show essential details, and for those that stop just before crucial events, and those that start just after crucial events!
- the quick cremation of crooks’ body
- the simple fact that there were no eyes in the sky (drones, CCTV, guards…)
- the use of text messages by law enforcement spotters instead of, e.g., walkie-talkies
- installing assets at strategic places in the investigation to steer the outcomes and hinder progress
- and this list goes on and on…
and the more layers get aligned precisely to allow 3+8 bullets through, the lower the probability that the attack happened by chance…
so, not only is it “difficult to accept that all these holes aligned up such that 3+8 bullets got through”, but it comes down to who had the power to align all these cheese layers such that these bullets went through unhindered?