Lampard is not a successful coach who has a lot of experience, on the contrary, Lampard has failed to manage several teams and at the moment Chelsea has no other choice so for a while they appointed Lampard as coach.
and I'm sure that for next season Lampard will be replaced and Chelsea will have to improve a lot if you don't want a bad season like this to happen again.
in fact Chelsea had made a mistake since the start of sacking Tauchel, Chelsea's management was very impatient when the team's performance was declining and did not want to give the coach time to improve, and now they are feeling the bad effects.
I would also say the same about Lampard, of course because he is a coach who has not experienced enough managing a team as big as Chelsea even though he is a former great player for his club.
Lampard's coaching skills need to be honed and he needs to be experienced enough at a few other smaller clubs for his impact on the team to be really good. There's a lot of pressure for him to deal with at Chelsea which is likely to miss his second chance. So I don't think Lampard will be good for Chelsea's current state, to be honest he isn't worth it yet in my opinion.