Before knowing the usefulness of the 5 frame nuc, you need to know what the 5 frame nuc contains?

    BEECASTLE 5 FRAME NUC

  Some of the reasons include the following:

• A nuc can serve as a nursery for raising new queens
• A nuc provides you with a handy source of brood, pollen, and nectar to supplement weaker colonies.
• A nuc colony of bees can be sold to other beekeepers — they're a fast way to populate a new hive.
• A nuc can be used to populate an observation hive.
• A nuc can be used to house a captured swarm of bees.
• A nuc can be used to house a supply of bees used for bee-venom sting therapy.
• A nuc in the corner of a garden can help with pollination, and it can require far less maintenance than a regular hive.                                                                                                                 Reference material:《Beekeeping For Dummies》