The emphasis of the IDF has been on functoning as an occupation force. This has been going on for decades. An occupation force is basically a police force, with the mentality, tactics and strategies involved. Even elite combat units are forced to spend stretches in the occupied territories, performing shameful tasks like cvilian population control, guarding colonists from locals and to much lesser extent trying to keep colonists from terrorizing locals, shooting at children and other civilians, etc. this state of mind of the IDF as a tool meant to help Israel maintain its occupation and colonization instead of being a real fighting force has helped reduced its effectiveness and quality to the extreme low levels we see now.
from the article: Caught with its pants down