Mishpacha newspaper reported about a new community called "Green Park" (a new neighborhood in Modiin Ilit). The residents of the neighborhood appointed a Rav named Rav Ovadiah Yaavetz. Rav Yaavetz went to the gedolim to get their blessings for his new position.

Rav Kanievsky did not just give him his blessing, but also gave him some instructions. Rav Kanievsky said, "Every community needs to have a Rav - someone who will guide them. Without a Rav, a community cannot succeed, as people will breaks fences that earlier generations established.
A Rav needs to know that he must work for the success of those in his community in Torah and yiras shamayim. This is the first thing a Rav has to do."

Because Rav Yaavetz lives in Bnei Braq and not in Modiin Ilit, Rav Kanievsky addes he should be in Green Park neighborhood as much as possible. "Even though you live in Bnei Braq, you should go spend the first Shabbos in Green Park, right away, to be with your community."

In many new communities it is common for shuls/communities to hire a Rav on a part time basis. Often the Rav will not move to the community but come once in a while to give some shiurim during the week and come for a specified number of Shabbasos every month.

In my shul, our Rav still does not live in RBS, but he comes almost every single Shabbos (he only does not come once in a very rare while), and is in the shul almost every single night giving Shiruim and guidance to members who need to talk with him.

Rav Kanievsy is saying that for a Rav to be able to do his job successfully and guide his 'flock', he has to be able to develop relationships with the members, and that takes presence. He has to be there as much as possible for that to happen.