Should registration be optional on an e-commerce site?

I am developing an e-commerce web site which will sell tourism services (airport transfer, accommodation, excursions, etc.). I am on a path here that I need to decide if I will provide a membership system or not.

From the user's perspective, the following two approach is possible:

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  Registration: A user should register for an account and then she can purchase online. Then, for the next time she can come to the web site, log in and purchase w/o entering the personal details again. Also, the user will be provided with a portal in order for her to keep her personal information up to date. Also, this approach makes it easy to provide a management portal for making changes on current reservations. One downside of this approach is registration is annoying and can scare the user away. If I choose this road, I will provide a way to use OAuth but it still can be overwhelming.

  
  


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  W/O Registration: A user can come to the web site and purchase a service or product without needing to register or log in. If the user needs to purchase another time, she needs to enter her details from scratch. These two purchases are completely separate from each other. They won't have a relationship and one cannot affect another.

  
  

I've considered mixing the two options and provide a way to choose but I do not have time for this. I need to choose one and go from there.

Do you support either of the above approaches or have a different idea?

Answer

Smashing Magazine published an article about a year ago called Fundamental Guidelines Of E-Commerce Checkout Design. One of the points there (No. 10) was that registration should be optional because:

• "customers already have a myriad of user names and passwords to remember and don’t want to create an entirely new account just to buy one or two products from an online store";


• customers "expect to be spammed with marketing material, even if they explicitly declined to sign up for a newsletter during the checkout process", i.e. "Account = Newsletter";



• "customers likely realize that you’re storing their information indefinitely";


• "signing up for an account also takes time";


• "customers just don’t understand why they need an account to buy a product".

If you still want to have accounts for tracking purposes or whatnot, this is the advice they give:

You can set their email address as their user name and fill in the account information with their order details. This way, the customer isn’t forced to create an account but has an easy way to do so after completing their purchase. (Remember to explain the benefits of having an account.)