I don't know if Frank Lampard will be really good for Chelsea, but maybe this is just the first step to take Chelsea in a good direction while contacting some of the best managers. This is a second chance for Frank Lampard which he should be able to take advantage of, he has a good job to bring the team to good performance, this is an opportunity because Chelsea are not in a good position.
Even if Lampard doesn't make it, this means he'll only get that short-term termination, but I think he'll stay until the end of the season. There is a chance that Lampard will stay if in fact Chelsea can get in good form for the rest of the season.
Frank Lampard wasn't so bad in his first time as Chelsea manager, probably with the available players now and the quality of the squad their is a better probability of doing better with this second chance. The objective for the remainder of the season will be to make European football and if he can turn the situation around till the end of the season their is tendency of getting a new deal at the end of the season.
Maybe, Chelsea doesn't have many options with very little time. which in the end, Lampard lined up to become interim coach. I don't think it's too bad, maybe Lampard can prove that he can bring Chelsea to change. and like you said, this is a second chance for Frank Lampard.
IMO, he just needs to create an ideal system for Chelsea players. I mean, Lampard just needs to correct what Potter is lacking. because in terms of the quality of the players, Chelsea has it. it's just that, the obstacle for Chelsea players is that there is no teamwork. That's why I said before, we don't know what happened in the Chelsea locker room with Potter. So, let's wait for Chelsea to play their game under Lampard's tutelage. after all, he is only a temporary option until the end of this season. Nonetheless, I'm pretty sure Nagelsmann will take over at Chelsea next summer.