Building backlinks slow, steady, gradually and google indexing....

Ok. I have a question. Rule of thumb is to build backlinks slow and steady or whatever. To make it look more natural or else you run the chance of your site getting "sandboxed". However, if google is indexing our backlinks at different times (sometimes a couple days, sometimes a couple weeks/months) how can it be so natural?

Two examples....

If I'm doing the slow and steady approach, doing about 50 or so per day... what happens if they index them all on day 80 (i know that's not realistic but i'm just asking)?

Also, if I build 500 backlinks in one day.... google is obviously going to index them all at different times. All 500 backlinks will not be indexed at the same time.


So how is it possible to "look" natural to google? I don't even worry about the amount of backlinks I do per day like I used to. I focus more on the backlinks I build to be diverse. Am I wrong? Should I still be building links gradually?