There are still hiring and human resources managers who treat candidates and applicants like a commodity. This is a big risk in a market where great talent is not easy to find. Well, let me correct myself. I should say it's easy to find people - but very difficult to hire. It's a seller's market in Thailand; the seller is the candidate offering his service to an employer.
So you wonder why the hiring company is not going to the extreme, to present their company and the job opening in the most positive way. Recruitment is also a selling activity in Thailand with an unemployment rate of 1%, and where you only chance to get people is to steal them from someone else.
"You will hear from us within a week" must be the most common job-search lie there is. Why don't they honestly tell you "It will take us a few weeks to interview everyone and get back to you."? You can give an employer a week more than they told you it would take them to respond after an interview. A bait-and-switch a la "It turns out the Senior Technical Writer job didn't get approved, but we have a regular Technical Writer spot open at $20K less that would be perfect for you!" is always a reason to run. No employer will ever treat you better once you're employed than they treat you as a candidate. Not everyone deserves you talents -- hold out for the people who do!