Why do forum members lock there threads ???

[MrSPliff]

Anyone shed some light

[1715351768]

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[NotFuzzyWarm]

When done by the OP (Original Poster) it is because the topic has been fully answered and discussed to death.
More often threads are locked by the Moderators and that is usually because it is seriously off-topic or in the wrong section.

[MrSPliff]

But sellers seem to lock when they post

[Lutpin]

But sellers seem to lock when they post

Some of them don't want people commenting on their sales.
In most cases, this is a bad sign and you should stay away from these sellers.

[susila_bai]

Who ever have created the thread with the topic and when the topic solution gets cleared , so after the OP of the thread gets satisfied with the thread topic he closes the thread as their should be not spam posting because their are so many users who just to reach the signature campaign posting requirement they just post the same reply repeatedly to avoid this that thread gets lock.

like now that your question got cleared so now you can also lock this thread so that their should not be useless posting spam to this thread.

[MrSPliff]

I thought it because there are scamming

[Velkro]

Some of them don't want people commenting on their sales.
In most cases, this is a bad sign and you should stay away from these sellers.

Agree they have something to hide then and talk only by private messages.
Its shady action.

[MrSPliff]

Only reason I asked as I was intrested in buying a product but he says bump then locks right away

[sportis]

Only reason I asked as I was intrested in buying a product but he says bump then locks right away

That means that the OP wants to keep his thread in a good place in the daily ranking in the forum so that to attract more visitors but for some reason he does not want anybody to comment on it. If the reason is not that he wants to keep it 'clean' for anything irrelevant, then it's almost sure that something he wants to hide and that's a good reason to not make a deal with him.

[LTU_btc]

Only reason I asked as I was intrested in buying a product but he says bump then locks right away

It means that OP don't want to see posts by other people made in his thread. If seller thread is locked, you have to contact him via PM or other provided contact information. But before dealing with seller you have to check his trust ratings, previous deals made by him. You have to be very careful because forum is full of scammers.

[arjuna BTC]

i think because the treads is already exist, and out off topic

[pealr12]

I thought it because there are scamming

Maybe yes, there are only few options why someone lock his own thread, its because it is already answered ,second the comments are the same,  and lastly its because of.planning to scam others .

[isen]

I have no problem with this, in fact, I am glad we have this option, signature spammers can be very annoying, and they are wasting OP's time with their nonsense posts.Of course, you can create a self-moderated thread if you want to keep them away but most of the times this is a red flag, and you will be accused as a scammer.

[botany]

I have no problem with this, in fact, I am glad we have this option, signature spammers can be very annoying, and they are wasting OP's time with their nonsense posts.Of course, you can create a modified thread if you want to keep them away but most of the times this is a red flag, and you will be accused as a scammer.

It is not a modified thread, it is a self-moderated thread. 
Even if somebody does create a self-moderated thread, you always have the option of creating a duplicate thread.

[isen]

I have no problem with this, in fact, I am glad we have this option, signature spammers can be very annoying, and they are wasting OP's time with their nonsense posts.Of course, you can create a modified thread if you want to keep them away but most of the times this is a red flag, and you will be accused as a scammer.

It is not a modified thread, it is a self-moderated thread. 
Even if somebody does create a self-moderated thread, you always have the option of creating a duplicate thread.

typo!
thanks for the correction 

[Thekool1s]

There are 2 reasons, If a Sr + Member locks a selling thread, in most cases it would mean he is trying to stop the Signature Campaign Spammers, They don't have any interest in their product but are only posting to get the Signature revenue, If a newbie locks a thread the same may be the case but there are high chances that something illegal would be involved plus they can scam easily. Also if the thread is not self-moderated and the OP thinks that the thread has gone way out of context, He/She May lock the Topic. There is no specific reason to locking the thread, Different scenarios dictate the terms. Just be careful when dealing with newbies who lock out their threads.

[nydiacaskey01]

Anyone shed some light

They lock threads to avoid spammers and also hijacking of threads. One good example is the for sale thread of TheButterZone like this one [WTS] Contents for a small thrift store for you or for charity and TheButterZone explained on the very first post why the thread is locked https://bitcointalk.org/index.php?topic=636950.msg7102804#msg7102804

There's Pros and Cons on this style of selling items in a forum, there is no problem if the seller is very well known, but if its someone like a newbie or one with no trade history its suspicious why transaction needs to be private.