次第 after a noun says that the noun decides how things turn out: "depends on", "is up to". The noun takes 次第 directly, with no particle in between, and at the end of a sentence it is or .
。
The result depends on your effort.
。
Whether you succeed is up to you.
。
It depends on your answer.
A verb comes in as a noun with , "way of doing", or as a question with : , .
次第で in the middle of a sentence
joins the deciding factor to what it decides, and the second half says what changes with it.
、。
We'll change the plans depending on the weather.
、。
The result changes depending on how you do it.
、。
Depending on how you look at it, life can be enjoyable.
次第では
picks out one possible case: depending on the factor, a particular outcome may happen. The second half usually ends in
or
, and the outcome is often one you would rather avoid.
、。
Depending on the situation, it might be cancelled.
、。
Depending on the other side's attitude, we may break off the talks.
次第 or によって
says the outcome is different for each case – each shop, each person. 次第 says one factor decides the outcome, and fits a result that hangs on effort or a choice.
。
The price differs from shop to shop.
。
Whether you pass depends on how hard you work.
After a ます-stem, 次第 means "as soon as" (, "as soon as it arrives"). That is a separate grammar point.