Backlinks continue to play an important role in website rankings. If links appear to the resource, it means that it is popular with the audience and can claim high positions in the SERP.
On this simple principle, as before, the search ranking logic is built, but with its own significant nuances. First, now the reference factor has ceased to be an absolute dominant. This means that backlinks to the site are still important for promotion, but they no longer work on their own, but are taken into account in combination with other ranking factors.
Link building is carried out with an eye on the algorithms - Google Penguin. For several years this filter has put things in order in the issuance and eradicated the situation when the possibilities of search promotion were 90% dependent on purchased links. By 2015, exchange trading in backlinks reached unprecedented volumes. Those sites that were able to massively purchase links to the forum link building service and provide themselves with a short path to the top ranked better. Naturally, in such a scenario, the quality of sites in the search results faded into the background.
Today, link spam has ceased to influence search results, and link building has been approached as carefully as possible.
An important condition for effective link building is the systematic dynamics of the link profile - when links grow gradually without sudden jumps. Bursts of activity (backlinks appear frequently and in large volume) can alert search algorithms. Their reaction in this case may be different: dubious backlinks will either simply not be taken into account when ranking the site, or they will be identified as a link explosion and will result in a filter being applied.
The optimal dynamics of building backlinks is a purely individual matter. Here there is a correlation mainly with the trust of the site, its traffic and the current link profile. The higher these indicators, the more actively you can work with backlinks. Much depends on the donors - the resources on which links are placed. The more trustworthy and relevant they are, the less potential risks for the recipient site.
Website trust is a fundamental ranking factor. The higher it is, the easier it is for pages to rank high in search results. You can pump up the authority of the site, including through backlinks from trusted sites. This parameter can be estimated from a potential donor by indirect signs: domain age, traffic, number of indexed pages, presence in trust directories, etc. But all this will give only an approximate picture.