Why are customers 'checking out' before actual checkout?

E-marketer announced this week that nearly 60% of US online retailers are seeing cart abandonment rates of over 20% this year. A study by PayPal and comScore found 45% of US online shoppers had abandoned shopping carts multiple times in just three weeks.

Reasons for cart abandonment vary and some are due to usability problems. Mercedes Sanchez Usabilidade has seen in Brazilian usability testing that many consumers abandon the purchase because they are stuck in the registration forms. They cannot register on the merchant website due to usability problems found on the forms.

What problems do you see in your country?