No. 1, set different voucher value and min. spend to encourage customer to hit higher amount for bigger voucher.
No.2 is to set the validity period of Vouchers to attract customers to buy as soon as possible within the validity period to enjoy the discount;
No.3 is to ensure the value of the Voucher must be attractive, generally speaking, it cannot be less than 5% of the order amount. For example, if you set a $5 Voucher, the min. spend for use cannot exceed $100, and the min. spend for $10 Vouchers cannot exceed $200, otherwise the attractiveness to customers is too small to be effective.
