Does requires imply after?

[greyhound-003]

^{(Note this is a re-post. GitHub auto-flagged previous discussion as possible spam - friendly platform...)}

Having read, the docs and #810 the relation between requires and after is still not clear to me.

It seems, requires is for plugin installation and automatic removal (if not used anymore) and after determines the load order.
Does that mean, in most cases I need to specify both for proper sequencing?

Example:

  use 'wbthomason/packer.nvim'
  use {
    'hrsh7th/nvim-cmp',
    requires= {
      'hrsh7th/cmp-nvim-lsp',
      'hrsh7th/cmp-buffer',
      'hrsh7th/cmp-path',
      'hrsh7th/cmp-cmdline',
      {
        'saadparwaiz1/cmp_luasnip',
        requires = {
          "L3MON4D3/LuaSnip",
          tag = "v<CurrentMajor>.*"
        }
      }
    },
    config = function() require("config.nvim-cmp") end
  }

Intuitively, it should be clear all child dependencies need to be installed and loaded each time, before hrsh7th/nvim-cmp is installed/loaded. I rarely have seen someone making use of after.
So: Do I need to add after expressions here as well?

[nyngwang]

FYI: I never use after and never encounter any problems.