Avoid at all cost if you are confident in your own ability
Pros
To be very honest, none.
Cons
Poor professional service culture because of a lack of exposure to industry best practices and experienced senior technical personnel (ranging from junior all the way to management). Too many egoistic "leaders" in management (middle and senor management alike) whose only skills are in managing upward and painting an overly optimistic picture of the ground (to put it in another way - delusional). Majority of the old timers or so-called "loyal" employees who stuck around were simply because they do not have the relevant skills to land a job outside of their circle (which, to be very honest, is a big red flag considering the wealth of exposures you are supposed to be able to get by being in a Big4). They are then somehow promoted into middle and senior management positions (dont be surprised, it is simply how a Big4 firm operate, unless you are extremely bad, its almost certain that you will be promoted) and continue to perpetuate the poor culture they exploited to get to where they are. At the same time, too many good people have left or are leaving because of the poor culture and because tech expertise, or even proper consulting skills and professionalism (which should be a mandate within Big4) is simply not valued. Even when we had good hires from the private sector, they tend to leave quickly and fed-up with what they experienced. A huge red flag that something is truly wrong. Many in the middle and senior management seem to be focused on bureaucratic theatre, implementing more red tapes and bureaucracies (to justify the need for their positions) rather than leading and solving problems at the working level or even work towards improving current work process and be a thought leader within their field (which again, is something that should be done by a Big4 management). Perhaps because they do not possess the necessary competence to do so, or because their careers are vested in the org having a bureaucracy first culture. Just to add-on, imagine the "leaders" complaining and blaming his/her employees for not being loyal, rather than trying to understand what exactly is the issue, or even try to get some sort of feedbacks across all the working levels. And even when they do ask for feedback, the immediate response was to cut off the employee and attempt to justify themselves (before the employee can even finish giving their feedback). Lastly, joining a Big4 is suppose to give you multitude of industry exposures, thats the supposed value-add of going to a BIg4, in exchange for the low-pay and long working hours. The "leaders" simply do not care, the less exposure you have, the less exit opportunity you have, and the more confident the "leaders" are in being able to "retain" (or trap?) you within the firm, or even within the team (job rotation request can be made, just dont expect it to be approved).