The saying "I can understand English but I can't speak" is so commonly used by Turkish people that it would be fair to state that not being able to speak English has almost become a syndrome in society. This study delves into the causes of this syndrome. In two state high schools, 293 high school students filled out a questionnaire including Likert-type items about the possible causes of this syndrome, and an open-ended question aiming to reveal their suggestions on how they can improve their speaking skills. The analysis of the quantitative data was done by means of Statistical Package for the Social Sciences (SPSS) 23, and the responses to the open-ended question were analyzed through content analysis. According to the results, it is commonly believed that they cannot speak English because of the focus on grammar rules in English lessons, differences between English and Turkish, lack of experience abroad, limited speaking practice opportunities outside the classroom, feeling anxious while speaking English, use of mother tongue by the teacher and the course books which do not include colloquial English. Therefore, some of the participants suggested having communication driven lessons and engaging in out of class speaking practice activities as ways of improving their speaking skills. It is hoped that such studies will help better understand the sources of failure in English as a Foreign Language (EFL) speaking, and begin to solve this problem more effectively.