Second language learners today seem resistant and have little confidence in their ability to learn English, what are the reasons from your point of view?

If they have a good teacher, provided with enough learning resources, correct guidance and motivation, the ESL students are even better than native speakers in terms of their knowledge of English grammar and vocabulary. 

This is due to many things.The lack of using English inside classes.If teachers speak , students will say that they don't understand.the whole society is fond of exams not actual learning.The4 skills aren't used fully.If teachers and governments pay due attention to the1st year primary.the result will be better

to be honest, there are many reasons behind that fact. I think that the most important one is that their teachers in the first place lack that confidence and knowledge because they were taught by the same type of teachers that they represent to the students. It is a kind of endless circle. To breack it, you have to start with the teachers not the students.

No, this is not the case with all2nd language learners but yes there are a few who feel like this.There are various reasons for the lack of confidence- sometimes learners find it very difficult to learn2nd language, as the proper way of teaching isn't being followed.
lack of curiosity is another reason.
A trainer has to arouse curiosity first in learners regarding the language.
When learners become curious they will explore several things on their own and further want to clear their doubts from their instructors.
learners must be exposed to situation based English as this will improve their speaking as well as make learning interesting.