@Yueehs,
Most tests are paper tests and their design uses translation to determine "accuracy". Since the teachers are often not native speakers, this determination of accuracy is anything but. Time wasted on translation is time that could be better spent developing fluency and actual understanding of the target language.
Test also focus on grammar and the grammar that has been taught/is being taught is terribly inaccurate. It leads to disfluency among students because many of the rules have little or nothing to do with English.