An idiom meaning something is neither one thing nor the other—unsuitable for the available options (literally, ‘too short for a belt, too long for a sash’).
彼の提案は斬新だが実行性に乏しく、帯に短し襷に長しという印象を受けた。
His proposal was novel but lacked feasibility; I got the impression it was neither fish nor fowl.
このサイズの服は帯に短し襷に長しで、どちらの用途にも合わない。
This size of clothing is neither here nor there—it doesn't suit either purpose.
予算も人手も中途半端だと、帯に短し襷に長しの状態になりやすい。
With only half the budget and manpower, things tend to end up being halfway—neither effective nor practical.