GTM Topology Records

Hi Experts, I am having some confusion on the longest match option of GTM. What is the use of this longest match option, if GTM has to check all the records, even wildcard record and then finally decide based on the weight/score. So what i found from the gtm guide and f5 articles is that,

if i have 2 topology records, one is specific and other is wildcard, both having same weight, GTM is going to to Round Robin because they have same weight.....

if the wildcard has higher weight, wildcard record will be selected, even when a specific record is present.

So what is the longest match doing here. what is the real use of it...Anyone?