Attract more transfer passengers

What is the secret to attract more transfer passengers from an airport point of view? The answer depends on whom you ask. Retailers they will tell you how important a great shopping, food&drinks, and entertainment experience is. Architects will insist on great terminals. Operations will tell you that it is about minimum connection time, short walks, and in particular bag processing. The latter being important because frequent travelers have blacklists of airports they avoid if they can.