have no staying power

to lack endurance; not to be able to last. Sally can swim fast for a short distance, but she has no staying power. That horse can start fairly fast, but it has no staying power.

Common Names:

Name	Pronounced	Usage
Staci	STAY-see	English
Mihaela	mee-hah-YE-lah (Romanian), mee-HAH-el-ah (Croatian)	Romanian, Slovene, Croatian, Macedonian
Darja	-	Slovene, Czech
TÜLay	tuy-LIE	Turkish
Armour	['a:mə]
Raquel	rah-KEL (Spanish)	Spanish, Portuguese, English