I know that not all verbs have a perfective counterpart, while there are others which are perfective-only.
However, some verbs do have both aspects, but many times dictionaries don't indicate their counterpart directly.
For example, the verb тянуть. This verb spawns many derived verbs, yes. Растянуть, вытянуть, натянуть. However, these prefixes add a new meaning, and thus they don't just form the perfective counterpart of тянуть.
On gramota.ru, the definition of тянуть does not cite its perfective equivalent. Like other dictionaries.
Then I found, on cooljugator.com, a link to the verb потянуть as the perfective equivalent of тянуть.
After checking the definition of потянуть on a digital Толковый словарь русского языка, that verb is described as
My question is: when a dictionary does not link to the perfective counterpart of a given imperfective verb, what does that really mean? That the perfective counterpart is not important? Or that the imperfective verb has no true perfective counterpart without changing slightly its meaning?