I had this issue with a knowledge check in our last session. Such checks do not require proficiency, everyone can try them. The paladin wanted to know if he could recall anything about a god the group had learned about. After I asked for an Intelligence (Religion) check and he failed (his Intelligence 8 did not help, even though he had picked Religion in paladin school), next the wizard tried, and after the wizard failed, the monk, and that failing, the fighter.
The game has group checks that one can use if the group tries to achieve something as a group. But in this case, it originally is not a group undertaking; and it also would not make sense that two people out of four need to know something, for the group to know something. And because the best character's skill is always more likely to succeed than a group on average, where everyone else is worse, mandating group checks here means the players would be better of for just one of them trying to remember something. But that seems to make no sense.
Most characters do not have that many skills to pick, so my players tend to focus on those that have most impact on gameplay, like stealth, perception, investigation or athletics. Knowledge skills other than Arcana for wizards are picked mostly for roleplaying reasons. For a classical party of four like ours here, against a Medium Difficulty (DC 15) check, the one character that has the knowledge skill has a 35% chance to succeed. The wizard has a 45% chance. The other two characters are not proficient and at 10 Int have 30%.
Even with those measly values, the chance that at least one of them will get there for a Medium difficulty check is about 83% (thankfully, they don't have guidance, or it would be well over 90%). That is too high for my taste -- for example, combat is calibrated around a 65% to hit chance: enough to often have the satisfaction of success, but still with a large enough risk of failure to keep the rolls interesting. With 83%, it feels more like you expect to succeed, and not making it is a let-down after all this effort.
Does anyone have good, practical ways, to avoid this issue? I've thought about only allowing rolls for those that have proficiency, but that effectively would limit it to a single character, and the players would probably deem it unfair. Or I could just accept it (my current approach).