1) MONEY - The base salary make living really difficult since they keep it consistent in every state even though the cost of living in CA is vastly different than CA. It can be hard to succeed in sales so if you don't succeed fast, you don't get commission.
2) POLICY - The policy of wearing a full suit definitely works most places. However, in the Silicon Valley / SF area where most of the companies are wearing jeans and t-shirts, it doesn't always work out as well. Same with the general approach with the territory. In a start-up rich environment, it can be really hard to succeed when the companies in your small territory leave the area as soon as they are large enough to target. It can make it REALLY hard to succeed.
3) Management - not everyone is like Jeff.