But, in reality, do you find that, within your firm, different professionals render different levels or quality of service? This is pretty common, I think.
We find that people within a firm are pretty consistent overall but out of every 10 or so, there seems to be at least one person that seems more exceptional and one that seems sub-par.
Your firm or company should have base-line service standards that are applied to all customers across the board. All customers should be able to rely on treatment that is prompt, fair, respectful, and pleasant--even if the 'news' or 'deliverable' is unpleasant. This is reputation insurance if nothing else.
The base-line standards should hold true no matter who is communicating with the client or who is responsible for them--whether the "lead" partner or manager, an assisting partner, a first year associate, a file clerk or the janitor.
If you have people who are sub-par at service, without a doubt, this needs to be fixed. Your reputation is vulnerable.
But it might surprise you that now I'm going to state that not all customers should be treated equally.
Above your base-line standards (about which many firms don't even have documentation or training, much less accountability...) it's just not physically possible to treat all customers the same (silly little barriers like 'not enough time in the day' seem to prohibit this).
It's actually okay to give super-deluxe service to your very best customers, to give some extras to good customers, and to give your base-line (which I'd hope is still at least slightly above average) to all the rest.
Think of it like an airplane--but it's not just about how much someone is paying you (revenue) for the one ticket, it's how important their overall continued patronage is to you. Loyalty works both ways. Think about hierarchy in standby, upgrades, legroom (United has 'Economy Plus'), club access, and more. This doesn't mean an airline should be rude to coach passengers, but that each step up gets a little better.
Make sure your base-line standards are better than average. And make sure you know exactly who your "good" and "very best" are above that. (See my recent post Who ARE Your Best Clients? for exactly how to evaluate customers.)
Make sure everyone in your firm knows who's who, too, so that the right level of service can be delivered consistently from person to person. When anyone pulls up a customer in your database, shouldn't they immediately know if they are "gold" "platinum" or "executive platinum" so they can act accordingly?