The cost of too many logins
Every extra tool is another password, another set of emails and another brand the client has to recognize. Clients forget where to find things, and questions arrive at the firm that the software should have answered. Onboarding each client takes longer too, because there is more to explain.
A stack also spreads your brand thin. If most tools show vendor names, clients may never connect the good experience with your firm, even though your team does the work behind each one. The credit goes to the logos on the screen.