There is probably no such thing as too much marketing, but only if it's effective.

Meaning, if marketing is poor/misjudged/fails to reach the audience, etc. – is ineffective – then yes, it's money wasted therefore too much of a bad thing.

Measurement is everything. If you know what you want to achieve and have devised a strategy to reach the goal, each tactic can then be measured for effectiveness. An ideal balance will be reached – neither too much nor too little – just the right amount to achieve the goal.

The simplest way to answer this is too much is the point at which the money you're spending STOPS working to bring you profitable business.

In other words, if you need say $5 in sales for every dollar you spend in marketing to break even (assuming say a gross margin of 20%) ***insert your own figures here. Then on average your marketing has to deliver that. If ROI drops to $4 then you've either got the mix wrong or you've hit a point of too much based on the business you get in exchange.

Of course this is incredibly simplistic because it may take some time for marketing to become effective in a new business, you may have to invest some up front before you start getting a business flow in exchange.

And if you're hungry, and marketing keeps delivering a return, and you can continue to expand then there is never too much marketing.

However, there can be TOO much communication which is masquerading as marketing. I find there are too many companies out there now who harvest your email from a promotion or 'free' offer and then absolutely bombard the crap out of you with daily emails without ever checking if you were actually interested in the first place.

My recommendation to you is make sure you have some good 'antenna's' or feedback loops set up in your business. Then make sure you're checking with new and existing customers what their needs and wants are in terms of contact and then customise your outflow to match their needs and wants. If you see a jump in lost customers(churn rate) make sure you're doing exit interviews and see if they're leaving because you bombarded them.

It depends how scalable and what type of niche your product is in. If you are a specialised b2b company you are only going to have a specific number of customers, for example if its a niche product with 1000 customers. If you are a main stream market like a mobile phone or a supermarket you can spend 150 million a year on advertising in Australia, yet the b2b might only spend $10,000. So my answer is it depends on the company.

I have always felt that the perfect level of marketing would be where the prospects call up to complain that they are seeing too much advertising - but unfortunately never yet had that. Its really hard to achieve cutthrough to a customer with the number of channels, media, and other messages constantly rolling in so I would be inclined to too much rather than too little. That said usually you are restricted by budget and the time you can put into understanding all the different channels to ever do 'enough'