It was discouraging smaller accounts from moving over. Especially registered accounts. Also Hurting their Advisor and Introducing Brokerage business. Small Accounts become bigger and you can make up for non-profitable with Scale.
I received an email (two actually) from IB in which they announced that they won't charge inactivity fee starting from July 1st onward. I have one account with two account numbers and receive an email for each of these account numbers. They mention that the elimination relates to not only inactivity, but also if the account would not reach the minimum balance. As reason they state that this "aligns them with industry standards". Edit: see here: https://www.elitetrader.com/et/threads/ib-eliminates-inactivity-fees.360044/
Is the better fill quality somehow quantifiable? How much it matters also depends on the trading volume. I'm a big IB fan, but there are 2 things that for more passive investment (not trading) accounts can cost by magnitudes more than commissions or fill quality: 1. They don't apply tax treaties for dividend withholding on international stocks, in most cases; 2. They are much more aggressive lending stocks bought on margin, resulting in higher tax rates. They also don't reimburse the customer when they lend shares in taxable accounts, something that Fidelity, Schwab, and others do. I had to move assets into another account because they were lending out my municipal bond ETFs, which makes the tax-free dividends taxable which defeats their purpose.
That tax quirck only affect their US clients. Most jurisdictions don't tax dividends differently if the shares are lent out. USA is the exception.