By the time they <build> <'ve built> <finish> that thing, we're going to be the ones going over it.

[GhotiO |fɪʃ|]

It's from here (link).
Source: YouTube video "Bill Burr: Nothing Will Change With Trump As President | CONAN on TBS" by Team Coco

Bill Burr was talking about the wall that Trump was planning to build.
[First he spends some time talking about how long it will take to build such a wall and then he says this:]

• By the time they build that thing, we're going to be the ones going over it.

Is he talking about the start of the action "build"? Or as I suspect the finalization of it (it just makes more sense to me in this context)?
If the latter, wouldn't it make more sense to use the perfect aspect or the verb "finish"?

• By the time they've built that thing, we're going to be the ones going over it.
• By the time they finish (or even 've finished) that thing, we're going to be the ones going over it.

Thank you

 

[5jj]

• By the time they build that thing, we're going to be the ones going over it.

Is he talking about the start of the action "build"?

Probably not.

Or as I suspect the finalization of it (it just makes more sense to me in this context)?

Probably.

If the latter, wouldn't it make more sense to use the perfect aspect or the verb "finish"?

• By the time they've built that thing, we're going to be the ones going over it.
• By the time they finish (or even 've finished) that thing, we're going to be the ones going over it.

Yes, but we don't worry about such thing in informal conversation

 

[GhotiO |fɪʃ|]

Thank you, 5jj

Yes, but we don't worry about such thing in informal conversation

Following this, does A's last line work in this context? This is also informal conversation.

A [walks into the kitchen]: The vegetables are ready already? Oh, that's great. I'll eat some now.
B [washing raw chicken meat in the sink]: I'm also going to cook chicken.
A: Well, I guess I'll wait, then. Tell me when you cook it.
|my writing|

 

[GhotiO |fɪʃ|]

we don't worry about such thing in informal conversation

Could you explain it to me, please.
Does the choice of the simple aspect in A's last line work as well as Bill Burr's?

• A: Well, I guess I'll wait, then. Tell me when you cook it. (#3)
  
  
• By the time they build that thing, we're going to be the ones going over it. (link)

 

[jutfrank]

• By the time they build that thing, we're going to be the ones going over it.

Is he talking about the start of the action "build"? Or as I suspect the finalization of it (it just makes more sense to me in this context)?

Yes, of course, he's talking about the completion of the wall.

If the latter, wouldn't it make more sense to use the perfect aspect or the verb "finish"?

• By the time they've built that thing, we're going to be the ones going over it.
• By the time they finish (or even 've finished) that thing, we're going to be the ones going over it.

Yes.

Following this, does A's last line work in this context? This is also informal conversation.

A [walks into the kitchen]: The vegetables are ready already? Oh, that's great. I'll eat some now.
B [washing raw chicken meat in the sink]: I'm also going to cook chicken.
A: Well, I guess I'll wait, then. Tell me when you cook it.
|my writing|

Use the present perfect: Tell me when you've cooked it.

Remember, the present perfect carries a sense of a completion of an action denoted by the verb.

 

[GhotiO |fɪʃ|]

Use the present perfect: Tell me when you've cooked it.

Thanks! To me, it also sounded better, but why do you think Bill Burr used the simple aspect? As 5jj said, it's because "we don't worry about such thing in informal conversation", but in my example with chicken it's also an informal conversation.

Remember, the present perfect carries a sense of a completion of an action denoted by the verb.

Yes, just like here:

It's from here (link).

• By the time they build that thing, we're going to be the ones going over it.

But he still used the simple "build". Please, I don't understand it

 

[emsr2d2]

I suspect that our attempting to explain this is rather futile. Sometimes, the use of tenses can really only be totally understood by long-term exposure to the language (ie living in an English-speaking country for a few years).

 

[jutfrank]

But he still used the simple "build". Please, I don't understand it

The verb 'build' has an inherent aspect of completion of its own, so Bill Burr's present simple sentence is enough to get the meaning across.

 

[GhotiO |fɪʃ|]

The verb 'build' has an inherent aspect of completion of its own, so Bill Burr's present simple sentence is enough to get the meaning across.

Why do you think that's not the case with my sentence?

• Well, I guess I'll wait, then. Tell me when you cook it. (mine)
• By the time they build that thing, we're going to be the ones going over it. (Bill Burr's)

Both, mine and Bill Burr's, are in the present simple and both talk about the finalization of the actions: building and cooking, but Bill Burr's works while mine doesn't. What do you think I'm missing here? Thanks

 

[jutfrank]

Why do you think that's not the case with my sentence?

I don't.

Bill Burr's works while mine doesn't. What do you think I'm missing here? Thanks

I didn't say yours didn't work. I was advising you what to say—what works better. Use the present perfect.

Another feature of Bill Burr's sentence that yours doesn't have is the time phrase 'by' the time', which I think itself suggests a point of completion.