Here is my considerations about the topic: »Bands who are lacking singers«.

When you are seeking a leadsinger for your band, you are actually searching for a person who meets several criterias:

The person must be able to sing (and do it well). He/she has to remember the lyrics, keep the rhythm, etc.

The lead singer must be an outgoing person to be the frontman or frontwoman of the band.

Some bands prefer that the lead singer have a particular gender.
If the band seeks for example a male singer, then I see a problem. It seems like a lot of women like to sing, but only few men (men likes to play instruments instead of singing). Men offen say as a excuse: »I can't sing«.

If the singer don't play an instrument, then he/she offen do not much about music theory, and that could be a problem, when working with instrumentlists.

Instrumentalist only need to play their instrument well, and know something about music theory. (meet criteria 1 and 4). A good vocalist therefore must meet all 4 criterias. If you are an instrumentalist, you demand more from the vocalist, than you yourself delivers.

Take myself as an example: I am a man, I know music theory and I like to sing, but.... I am not an outgoing person, I'm quite shy and introvent person, and thats why I can't be the frontman of a band. I meet only 3 of the 4 criterias.

If you start with several singers in band, you can afford to lose one, and your band can make more interesting vocal arrangements.

I would find the singer(s) first, then find the drummer, bassplayer, and find the guitarplayer(s) last. Avoid guitarist who can't/won't sing (otherwise they contribute to less). In this place I only speak about bands with the traditional line-up: Vocals, guitar, bass and drums.

To keep the number of bandmembers low, each member must be able both sing and play to some extent.

Sometimes you have 2 guitarists, one guitar/vocal and one just guitar. That's not efficient. Let both guitarist performs lead vocals in turn (they must alternate). Let bass player and drummer perform backup vocals, because lead vocals are harder to do for a bass player or drummer than for a guitar player.

Sometimes 2 guitarist has got together and now they tries to find a vocalist, a bassplayer and a drummer. Perhaps they will find it hard to find the other bandmembers.

About me:
I am a danish bassplayer who also sing backup vocals and occasionally lead vocals. I am not able to sing lead vocals all the time, so the other instrumentalists must also contribute some lead vocals (at least the guitarist must). It is not a good idea to have person in the band who only sings (because this person will be unemployed if I do a lead vocal).

The singer(s) is more or less the same the band (from the publics view), the other members can be replaced and it is still almost the same band, but try change a vocalist, and you got a hole new band.