ようでは is a combination of the auxiliary verb 様（よう） ‘manner’, or ‘seeming’, and では, a conjunction that is frequently used as an abbreviation of それなら in expressing ‘if’. Due to this, ようでは itself often has the meaning of ‘if’, with extra focus on the fact that (A) is something unconfirmed, or only being guessed at. This may be translated as ‘if it is the case that (A)’, or ‘if that which seems to be (A) is true’.
In most cases, ようでは will be used to make an evaluation that if (A) is true, then some particular negative result will arise from it.
ようでは will primarily appear after verbs in any of their standard forms.

• こんな毎日（まいにち）同（おな）じミスをするようでは、いつまで経（た）っても店長（てんちょう）にはなれませんよ。
  If you keep making the same mistake everyday, you will never be able to become a manager.
• これらの文法（ぶんぽう）が分（わ）からないようでは、N2に合格（ごうかく）することはできません。
  If you do not understand these grammars, you will not be able to pass N2.
• これぐらいの高（たか）さで怖（こわ）がっているようでは消防士（しょうぼうし）にはなれませんよ。
  You can't become a firefighter if you're afraid of heights like this.

ようでは puts extra focus on the appearance or condition of (A), based on what is observable by the speaker. In this way, it is often the speaker’s subjective (negative) opinion about what they perceive to be true.