If you want a generalization, then generally delta:wyes are more common for distribution. With lower voltages there may be code issues with grounding.
A few issues:
Current distribution on the primary,
Switching surges,
Power back-feeds when a primary phase is lost,
Common practice and common utilization voltages,
Power transmission or distribution,
The number of primary conductors,
Ground fault scenarios.
A final generalization;
Vague questions such as this are often suspected to be homework and may be red flagged.
Bill
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"Why not the best?"
Jimmy Carter