It makes intuitive sense that customers who complete the trial* version of your software are more likely to purchase it, but it cannot be so easily deduced that the converse is true, i.e. that non-finishers are much less likely to buy.
A potential customer may use your software twice and purchase it immediately, or purchase it much later without ever finishing the trial. However, it would depend on the nature of your software, especially for games and one-use software like importers and converters.
Have you, as a software developer, seen any clear correlation between:
- Date of first use or download,
- Date of trial expiry (whether 30 days or 20 uses), which can be inferred from the date of first use if not measured.
- Date of purchase
One should also consider the % of buyers who purchased during and after the trial period. The conclusion drawn from this data would influence the optimal length of a trial period, the extent of crippling following expiry and the preferred method of trial limitation.
* fully featured for limited time or uses.
FYI, my question was closed on StackOverflow.com, so hopefully it is more suited to this audience.