Is it just me and my bad luck.. or is there a serious problem in the auto/racing world with people being able to stick to a promise date?

A few years ago, I sent my small block heads off to a celebrity machine shop back east.. He promised to return them in about 6 weeks.. after several phone calls and emails.. I got them back in 10 weeks..

Next up was the B1 heads I sent off to another celebrity machine shop (Rest in peace).. This time, it took over 3 months to get the heads back, but they were absolutely awesome when they arrived.

I ordered a set of T&D rockers for the B1.. I think they promised a ship date of about 2 weeks.. That whole fiasco took 2 months to receive..

Now recently, I ordered a set of custom made Williams valve covers. On a Tuesday morning, I placed the order and was promised over the phone that I would receive them by the end of that same week. We are now 4 weeks later and I still have no valve covers..

I know if I was to miss due dates and promise to deliver dates by more than a couple of days, I'd be out of work, so I was wondering how these companies get away with it.. Are we more patient as consumers than in other industries.. or are we collectively more stupid? lol

Whats your experiences with waiting for parts that never arrived on time? (back orders not included)