Only by practicing or repeatedly doing something can one become proficient or skillful at it.
For example:
If you want to learn a language, speak it as much as you can. Practice makes perfect!
A famous quote from the Irish writer, Samuel Beckett is:
"Try again, fail better!"
練習するか何かを繰り返しすることによってしかその物事に対して、プロや熟練にはなれません。
例
If you want to learn a language, speak it as much as you can. Practice makes perfect!”
「もし言語を話せるようになりたければ、できるだけたくさん話しなさい。「習うより慣れろ」です（練習が完璧をつくります）！」
アイルランドの作家、Samuel Beckett のこんな有名な一文があります。
“Try again, fail better!”
(さらに挑戦して、より良い失敗の仕方をしよう！)
Anything that can go wrong will go wrong (Murphy's Law)
If at first you don't succeed, try, try, try again
There are many ways to say this in English, although you may tweak your phrasing based on the context. For example, we all know that learning often occurs through "trial and error" and "practice makes perfect". However, a famous proverb called Murphy's Law states that "anything that can go wrong will go wrong" - which is another way of saying that in order to succeed, or make something perfect, many things will fail or go wrong in the process.
文脈に基づいて言いたいことを微調整するかもしれませんが、
英語では、これを表現するのにたくさんの方法があります。
例えば、私たちはよく学びには
“trail and error”(試行錯誤)
や
“practice makes perfect”(練習が完璧を生む)
があると知っています。
しかしながら、
マーフィーの法則と呼ばれる有名なことわざには、
“Anything that can go wrong will go wrong.”
(失敗する余地があるなら失敗する。)
があります。
これは、成功するために、あるいは何かを完璧にするためには、
たくさんのことを失敗するか、またはその過程で失敗するという意味の別の表現方法です。
Any of these two expressions can be used to express that making mistakes is inevitable when trying to learn new things.
1. Failure is the mother of success - This means that we must fail at something first before we become successful at it.
2. We learn from our mistakes
Both of these statements are two ways of saying the same things, which that when learning something new, we can learn from the mistakes that we have made.
2例とも、新しいことに挑戦するときには失敗はつきものだと表すときに使えます。
1. Failure is the mother of success（失敗は成功の母である）
これは、成功の前には必ず失敗があるという意味です。
2. We learn from our mistakes（私たちは失敗から学ぶ）
これら二つの文は同じ意味です。失敗をすることで新しいことを学べると表します。
Indeed, failure teaches success. However you have to learn from your mistakes to become successful. Above are two ways of saying the same thing- though focusing on the same aspect: learning from your mistakes.
That said, however, it is even better to learn from other people's mistakes.
We all learn by our mistakes' is a well proferred idiom, - though history begs to differ. As a piece of advice it is a very good phrase for English language learning as it encourages students not to worry about trying new ideas and experimenting with their constructions.
We all learn by our mistakes.
（私たちは失敗から学ぶ。）
は、歴史とは異なりますが、よく使われるイディオムです。英語学習者にとっては、失敗を恐れず新しい表現を試すよう促す言い方として、良い教訓になるでしょう。
The three sentences you see provided above are terrific ways to express to your listener that making a mistake is inevitable if we are trying something new. In the third sentence you will notice the term part of the territory. If something is part of the territory it means that it comes with whatever it is you are doing. So for example if you are studying at the university you can say that studying late at night comes with the territory.
上記三つの例文は、何か新しいことに挑戦するときには失敗はつきものだと伝える素晴らしい言い方です。
3文目には「part of the territory」という表現が使われています。これは「避けては通れないもの」を表します。例えば、大学で勉強しているなら、夜遅くまで勉強するのは「come with the territory（当たり前）」と言えます。
The first example is pretty easy to understand, you simply cannot avoid failure and it is inevitable.
Failure teaches you many things that are important to know in order to succeed, thus failing is a key to success.
Everybody fails =, even the most confident, famous, or popular people fail and have failed.
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