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@MHM Cisco World wrote:

For what lacp with one link!!!!!!!!!

There is no need and this lead to suspended state.

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Actually, as I've written, when I wrote they're not very useful, that would be in context of normal operations.  Besides the possibly of a single link being the case in a remaining link failure situation, as noted by @paul driver , I've defined single link LACP when converting two operational dual links from non Etherchannel to Etherchannel while attempting to minimize network operational impact.

If it's not obvious, what I've done, in the case of dual L2 links between a pair of devices, I identify the link currently being blocked by STP, shut it down, convert it to a single link Etherchannel, then no shut it.  I then shut down the non converted link, make it a member link, and no shut it.  Impact should be a single STP converge event.  So, it's not zero impact, but minimal impact.

I've also been in the situation, I setup a dual link Etherchannel, but second link isn't yet patched in.  So, configuration is for two member links, but only one active until the second is patched in.