Time restrictions do not function identically in all acts of worship. Treating an appointed prayer time as a legal envelope (ẓarf) indicates when the particular prayer can be performed, without excluding every other act of worship from that interval simply because the time is assigned.
For example, certain voluntary prayers can occur within the broad period associated with the noon prayer. Mere entry of the time does not therefore identify every prayer performed within it as that obligatory prayer; intention and other conditions remain relevant.
Core distinction: The time can provide the setting for performance while the identity and legal status of the act require separate determination.