In my opinion, there are numerous reasons why affiliates become inactive shortly after joining SFI.
The main reason is probably bad referral links. For example, some company tells them they will get such and such free if they complete three or four of some type of other offer. The potential affiliate then chooses to sign up for SFI just to complete this task but isn't really interested in SFI. I'm sure you've seen things like this on the internet.
A second reason is curiosity. Many people will sign up just to see what it is about and if it will work for them. They may think it sounds too easy and must be a scam. They may even search the internet for "SFI scam" and they will find unhappy affiliates who have posted negative comments about SFI and claiming them to be a scam. Usually this is because they didn't work the program and weren't successful, so they blame it on SFI.
Other times it's simply lack of motivation. Think about New Year's Resolutions. Probably half of the women around the globe made a New Year's resolution to lose weight. They will hit it hard and lose some weight the first few weeks or maybe even the first few months but then the excitement wears off, the results are coming too slowly, and they give up. Persistence is the key for them to achieve their goal but they don't have a winning attitude; the pessimist will quit before they can ever achieve their goal. The exact same scenario as above happens to affiliates but instead of a diet, they are working SFI and then losing their excitement after not seeing huge results after a few months.
This is probably just the tip of the iceberg, but I hope that helps.
In my opinion, there are numerous reasons why affiliates become inactive shortly after joining SFI.
The main reason is probably bad referral links. For example, some company tells them they will get such and such free if they complete three or four of some type of other offer. The potential affiliate then chooses to sign up for SFI just to complete this task but isn't really interested in SFI. I'm sure you've seen things like this on the internet.