For companies raising $1.5 mil or less, from my (very limited) anecdotal observations it seems like investors have a base usefulness that may or may not fluctua

For companies raising $1.5 mil or less, from my (very limited) anecdotal observations it seems like investors have a base usefulness that may or may not fluctuate as a function of the amount they have invested. It also may or may not fluctuate depending on how interesting your startup is, how much they like you, how often you run into each other at social functions, etc... From what I've seen (certainly a small sample, so may be wrong, curious to have others chime in) there are investors whose lowest possible usefulness (they invested the smallest amount they ever invest) still exceeds other investors' highest possible usefulness (however invested they would be if they were responsible for the entire round - $1.5mil or less). As a result I see the appeal of a party seed round - you increase your chances of getting investors who are useful by nature.