In which scenario is First-Class mail not recommended?

First-Class mail is designed for a variety of mailing needs, but it may not be the most cost-effective or efficient choice for non-time-sensitive promotional materials. Specifically, when the materials are not urgent or do not require quick delivery, other mailing options, such as Marketing Mail or Standard Mail, can be more economical and provide suitable delivery times.

Marketing Mail, in particular, is ideal for promotional materials that do not need immediate delivery, making it a preferred choice for businesses looking to engage customers over time without the premium costs associated with First-Class mail. Thus, for mailing promotional content that doesn’t need to arrive promptly, selecting another mailing service helps in managing postal expenses while still meeting marketing objectives.