Conversion conundrum

[windycityparrot]

A week doesn't go by that I don't get solicited for a (some) new conversion rate increase tool/plug-in/software/SAAS ad nauseum all promising 3% to 5% conversion boosts. So here's my question - why can't I just install 20 conversion boosting tools that claim a 5% increase in conversion and then convert at 100%?

[AmagArtwork]

Oh ... if it was only that easy. Everyone would be using them all.

[windycityparrot]

that's why every conversion increasing software is suspect and why god invented free 30 day trials