The phrase "major shortcoming" means a significant weakness or flaw in something or someone that hinders their ability to work well or meet expectations. Full definition
I have stated before that I am not a fan of loan deals to resolve major shortcomings. (westhamway.net)
Standard smoke detectors have a few major shortcomings, mainly that they're not all that useful when you're not home. (smarthome.reviewed.com)
A new Columbia Law School report reveals major shortcomings in how the UN aviation body (ICAO) interprets transparency and public participation requirements. (carbonmarketwatch.org)