don't know if anyone can pinpoint a so-called "sandbox", but is sure seems that google can unfairly penalize a site for a year and more so, yes, I would have to say that some sites get put in the sandbox and never come out again
I don't think it'll last that long. Is your site showing up when you search directly for it? I've had sites sandboxed for a few months. I also have sites that jump in and out of sandbox every other day it seems. Google can be crazy .
Yes, you can be in the sandbox forever. It really depends on what Google thinks; if they think you are a safe site they will take you out of it. I know a website I worked on took about 6 months to get out after link building and better content.
If a website in sandbox means lack of relevant backlinks. So it may be possible. So good backlinks will solve your this problem.
I think it's possible, it depends on your niche and how competitive the targeted market is... However my longest sandboxed period was 3 months for some how a competitive keyword, but right now am not facing any delaying problems specially with Google. Sandbox dose not exist for me anymore
i do not think there is ever a word 'sandbox' existed so the major thing you need to do is increase quality backlink and update your content to be unique and fresh then you are automatically out of the 'sandbox'...
I did not experience it myself but heard people talking about it that their sites disapeared for more than a year due to the Sandbox.
According to sources, some said that it can last up to 6 months. Myself I have only experienced once lasting up to 3-4 months. Not sure whether it can drag up to a year though.
It really depens on what you have done and everything is just theoretical. No one knows for sertan. Of course there is a way to test it. Do everything what google forbits you to do and then count how long it will take from them to forgive you.