What is happening arounf

Following are the scenarios I have experienced in the last 30 days. company A invites for all the rounds and says I am selected but says they do not have budget company B invites for all the rounds and says I am selected, but do not release offer letter, and HR guy says it is on hold cause still the US team could not approve the budget and asks to re call for every other day company C says I have cleared level 1 interview and they do not have slots for next round I am unable to understand, is it just me experiencing this or is it the same for others as well