AACSB or any other international accreditation requires process management; documentation in place, a commitment from top management and above all it has a cost associated with it... Many organisations they don't have process in place... and it needs time....

Any accreditation process is resource intensive (time and money), even more so if a culture of process improvement does not already exist in the program to be accredited.  If this is the case. the documentation and assessment  plans required to be successful will then be challenging.  In addition,  faculty (typically just a small group) are usually asked to assume this responsibility in addition to other duties when a collaborative effort is required particularly for curriculum mapping and remapping, and assessment planning, insertion and evaluation.  

So if there is not strong support from University administration for the accreditation effort by providing releases, budget allocations, additional staff or consultants, accreditation workshops and accreditation fees, many good intentions will be tabled for other  short term priorities. 

Hopefully the process of improvement exists among the faculty and is required, recognized and rewarded within the institution. The process of accreditation does demand time and expense, but most institutions are pleased to be recognized and listed among the accredited institutions and may even provide some support for this undertaking. 

Sometimes accreditation workshops are offered in conjunction with professional conferences or at regional locations. Just learning the details of the accreditation process may provide ideas for improvement for your own program. Actually going through the accreditation process may be work for a Department, but it may provide evidence to your Department and the Administration of the strengths, weaknesses, and needs of the program(s). Outside evaluation can be very useful to a Department in working with its Administration to strengthen its program(s). 

Agreed  with Carla Sampson, but will like to add that culture of institution can also be a factor especially in Less developed countries! Quality as reflected through indices is recent phenomenon. In resource constraint situations, funds for other activities like research may be competing factor with reporting quality! International Quality indices is very useful for students and other parties but it also add its share in overall cost of Education.

https://www.researchgate.net/post/How_do_you_define_a_university_accreditation?

Regards, Emad