In some cultures, students are embarrassed to speak in front of others, so I take this into account and don't call on these students in class.
This commonly-held belief about English language learners is particularly relevant to language instruction. I personally find the belief to be so unfounded (specious, really) as to be almost laughable for the reasons I will outline below. First, the belief is premised on the fallacy that there actually are (some) cultures where students are generally embarrassed to speak in front of others. Because individuals usually do not speak when alone (of course, there are exceptions as we do sometimes mutter to ourselves, but I would hold that even those who fervently support this belief would agree that most speaking takes place in the presence of others), if this premise were true, then there would have to be some cultures where individuals either never speak (except perhaps while alone and only to the mirror) or are always embarrassed when engaged in conversation. While the world is, admittedly, populated by thousands upon thousands of distinct cultures (many linguists posit that there are currently around 7,000 different languages spoken throughout the world), I have never heard of any culture where individuals do not speak at all when in the presence of others. Such a culture would seem to be completely at odds with human nature. Second, even if there are cultures where some individuals tend to feel anxious when speaking in front of groups (in fact, I would argue that in all cultures there are some individuals who are embarrassed to speak in front of others), this belief is built on a such a broad and sweeping generalization that it is almost impossible for it to be true, especially since the supposedly embarrassed students are completely unqualified (that is, in the numerical sense: not some students, many students or even most students). As Dr. Kris Gutierrez aptly pointed out, "there is more variation within groups than between groups" and so we would expect that within any cultural group, we should find individuals who run the gamut from timid and reticent to unreserved and garrulous, with all shades in between. Based on my personal experience, individual personalities play a far greater role in determining who sits in his chair looking down and who raises her hand trying to answer every question than do cultural tendencies. I have had students from societies in which our putatively easily-embarrassed students hail (such as China) who have talked my ear off and others from societies often stereotyped as outgoing and talkative (say, Italy or Brazil) who would hardly utter a word in class. I hope, then, that I have managed to deconstruct and demolish the first part of this "belief": it is inherently illogical and involves such an extreme overgeneralization that it cannot possibly reflect reality. Some might say that the belief is based on a grain of truth, but I have looked for that grain and cannot find it.
Next, I would like to turn to the second part of this belief to address the wisdom of not calling on students who may be embarrassed to speak in front of others, because such students do of course exist, even though they are more-or-less evenly distributed among cultures. I believe that this part of the belief is fundamentally flawed in at least two respects. First, even if some students do feel anxiety or become embarrassed when speaking in front of others, they must nevertheless be given meaningful opportunities to practice the language they are learning; otherwise, without practicing and producing the language, it will be impossible for them to acquire it and so the entire project will fail. If language instructors do not address the needs of all students (including those with performance anxiety), then the ignored students might as well not even show up for class, since completely ignoring students is tantamount to banishing them from the classroom altogether. Second, as we learned from Steele and Waters, many students are able to "rise to the challenge" when presented with challenging yet attainable goals and encouraged in effective ways (such as being told in a genuine manner that they have the ability to meet the challenge before them).