What is a Deadline?

(0)"Hey Gentleman, we got a big big big project."
"Oh mine, then we must plan it well!"
"Ok, lets put it 6 Months"
"Cool. with that we can really make a masterpiece"
"Ok, the first two month will be design stage"
"following 1 month, we review it"
"then the nxt one and half month, source it out"
"the last 6 weeks final assemble, and pack."

(1)"Oh crap, suddenly this one pops up, an issue from last project."
"No choice, we pull that back first, and solve this."

(2)"Hey, we need to do this small modification, can you rush for us?"
"Err...let me check my schedule."
"Ok, can, I push over those which are not in red to slot this in"

(3)"Hey, you busy?"
"I got several stuffs running on buffer, but...I guess it is ok, I do it for you."

(4)"Oh shoot! we left only 1 week for the design stage!"
"no choice. chop chop have the design out, and source all the stuff out."
"remember the urgent stamp."

(5)"Ok. finally everything is in."
"hmm...some issue here."
"Shoot, how come this?"
"think we left it over when we decided to change that."
"Argh... ok, promptly change it, and remember to update. ask the vendors to rush it out."

(6)"Hey! you promised me to deliver it in ** this timing"
"What caused the delay?"

Please continue your reading in sequence, (0)(1)(2)(3)(4)(5)(6),(0)(3),(1)(2), or in any sequence and collection you can imagine(if your imagination isn't killed by all your deadline), then slot in different character: your customer, designer, your sub-contractor,your sub-sub contractor, your customer's customers, the material supplier....your mom, your wife, your husband....etc etc...

And you know why is everyone running a tight deadline.