OK, since you insist, I will spell it out for you. 1) Deloitte has an established client base, including 98 of the FTSE 100, and over 400 of the Fortune 500. EY doesn't have the same calibre of clients ( yes this does exist ). And, for the clients it does serve, it focuses mainly on operational and process work - not exactly cutting edge cconsulting. 2) Probably the MOST important reason why EY BAS will never reach the level of Deloitte: It has failed to distinguish itself from its audit brand. Deloitte Consulting, as you know, is an independent comapny, with seperate buildings, leadership and business model. BAS's model, unfortunately, is still highly dependent on their audit practice - and this shows its symptoms in many areas - take recruiting for example. 3) Leadership at EY is confused. There has not been any consistent marketing, sales process or execution of work to create a brand. It seems like BAS has just desperately try to sell what it can - and where it can. 4) Deloitte is very strong Internationally: it ranks just behind MBBB in the USA, strongly in Australasia and is a leader by strength in Europe. BAS does not have the same global reach. 5) Lastly, well I dont have that much time to continue, Deloitte has an established, credible, strategy capability. Its S&O practice just split, and its Strategy practice is almost as big as the entirety of BAS. I know you might think that BAS does not compete with strategy work direct, but its a strong plus to have, even when you work in operations. EY, I'll give you this, has a cracking office on the river. But for everything else I would chose Deloitte. Hands down, every day of the week.