Google's John Mueller in this morning's video at the 22:47 mark said that building too many links in a short period of time is not an issue by itself but rather it is the types of links you are probably building in that time period. He said often it leads to links that are against Google's guidelines.
The question was If I started linking building and built 200 links in two days and before that, zero links in two years, would Google penalize the site?
John said "it is not the number in the period of time, it is really the type of activity instead."
Here is what he said:
(1) Building zero links for two years would not be penalized.
(2) If you are building 200 links in two days, it is not so much the number of links you are building in a short period of time, it is really the matter that you are probably building links in a way that would not align with our webmaster guidelines. Our algorithms might take action on that or they might ignore those links. On the other hand, our manual actions team might take action on that and apply a manual action.
So it is not so much the number of links and the time you are talking about. It is more the type of links you are building and the type of link building you are doing in general. If you are dropping links on random sites, if you are buying links, if you are exchanging links using some weird link network. All of those things would be against our guidelines which would perhaps result in 200 links being built in two days. And since our webmaster guidelines, we try to catch those algorithmically and ignore them. And we do from time to time try to look at these things from a manual point of view and we may take manual action.
So really, it is not the number in the period of time, it is really the type of activity instead.
Here is the video embed: