Ideally, what should the relationship be between (a) the problem solved by the lead magnet and (b) the problem solved by paid service or offering?

Articles such as https://www.searchenginejournal.com/lead-magnet-examples/265245/ recommend creating lead magnets that solves your audience's problem immediately. To quote "Your audiences are constantly looking for a solution to their problem immediately. If your lead magnet can fulfill that gap, you will be building an email list in no time." Here is my question: If one has a paid service or offering that solves a particular problem for customers, what problem should the lead magnet target to solve? In other words, how should the problem solved by the lead magnet relate with the problem solved by the paid service or offering? Here is a situation as an example: The paid offering is an online subscription service that helps investors manage their retirement savings. Here are some possible lead magnet types and examples: Type 1. Lead magnet offers the solution to the same problem in general terms Example: Lead magnet describes the steps involved in managing retirement savings Type 2. Lead magnet offers the solution to a part of problem tackled by the paid offering Example: Lead magnet describes how to analyze specific type of investments used in retirement savings account Type 3. Lead magnet provides the full solution for a short duration. Example: Lead magnet allows prospects to try the paid subscription service free of charge for a week. Type 4. Lead magnet solves a complementary problem Example: Lead magnet shows how to compare different brokerage accounts (brokerage accounts are commonly required to manage retirement savings). How does one go about assessing which lead magnet is likely to work best? What factors should be considered in choosing the lead magnet?