They don't care about you, the work, or their customers. All they care about is the value they can squeeze out of you. The quality of your work doesn't matter, and they don't care if they are working you to the bone. They just need the work to get done so they can maintain that sweet, sweet profit margin.
Bonuses are a joke. Most Taiwan-based companies will give you 2-3 months' salary as a bonus over the course of a year (albeit pro-rated for the first year). This place gives you just enough pocket change to maintain the substance abuse problem you developed since you started working there.