Ventajas
If you come in as a "high potential" and are very young, you are golden in this company. Once you have this label you can essentially do no wrong -- even if you perform poorly, it is perceived that you have just been put in a job that does not match your strengths. Also, if you want to come here and just be an OK performer and never be promoted, this is a good place to be. You can park here and be forgotten for 10 years without anyone noticing.
Desventajas
If you are not a designated "high potential", and there are many reasons that this can happen that have nothing to do with your actual real life potential or performance, then it can be very challenging to be promoted or even move laterally into positions that are seen as glamorous. Even if you perform very well, your raise and bonus will never compete with a high potential who does poorly. If this sort of thing gets under your skin, then do not come to Shell, because it is rampant -- there is a 2% ruling class that gets everything and if you are not in that club very shortly upon joining (again, many reasons this can go the wrong way -- for example if you have the wrong manager who runs the evaluation process the wrong way) then it will never change.