tested vs well-tried

tested and well-tried both are adjectives.

Word	Noun	Adjective	Verb	Adverb
tested	No	Yes	No	No
well-tried	No	Yes	No	No

As adjectives, tested and well-tried are synonyms defined as:

Other synonyms of tested include tried.

tested (adjective)	well-tried (adjective)
tested and proved useful or correct	tested and proved useful or correct
tested and proved to be reliable