It's so simple. A QR Code is encoded data. What do you want to encode in your code? If you encode your data Directly, no matter what, someone will be able to get at your data. Lots of readers, no need for internet access, etc.
Indirect QR codes encode data still. They encode a reference to the proprietary location of the data you want. With a regular reader (since for most indirect codes, they want you to download the proprietary reader as well) you will decode the data simply as a reference. A number, a code, a lookup. Or worse, a URL, but not the one for the site you want, one that references the database to look up what site you want.
Sure there are some advantages and disadvantages. If you use a direct code, you get less analytical intelligence about usage. However if you use an indirect code, your customers have to have the right reader for it to work. What is more important to you?
My terrible picture should explain how terrible this is:
Indirect QR codes encode data still. They encode a reference to the proprietary location of the data you want. With a regular reader (since for most indirect codes, they want you to download the proprietary reader as well) you will decode the data simply as a reference. A number, a code, a lookup. Or worse, a URL, but not the one for the site you want, one that references the database to look up what site you want.
Sure there are some advantages and disadvantages. If you use a direct code, you get less analytical intelligence about usage. However if you use an indirect code, your customers have to have the right reader for it to work. What is more important to you?
My terrible picture should explain how terrible this is:
