While a single nation-wide primary would essentially require pre-existing universal name recognition, and an enormous amount of money for nation-wide media buys right away, staggered primaries allow candidates to build national recognition via the cheaper (and generally assumed to be more virtuous) art of small-scale, in-person "retail campaigning".
- The same, highly non-representative places, always get an undue influence on the process
- Caucuses that are insanely inaccessible, require several hours of your time, and are basically impossible to participate in for many (most?) people
- Violates one person one vote
- Convoluted delegate math makes for very complicated strategic decisionmaking