There are disadvantages to be managed.
Competitive and expensive
Since pay-per-click has become popular, some companies may get involved in bidding wars that drive bids up to an unacceptable level. Some phrases such as ‘life insurance’ can exceed 10 GBP per click.
For companies with lower budget or narrower range of products on which to generate lifetime value, it might not be cost effective to compete.
Requires specialist knowledge
PPC requires a knowledge of configuration, bidding options and of the reporting facilities of different ad networks. Internal staff can be trained, but they will need to keep up-to-date with changes to the paid search services.
To manage a PPC account can require daily or even hourly checks on the bidding in order to stay competitive. This can amount a lot of time. The tools and best practice varies frequently, so keeping up to date is difficult.
Sponsored listings are only part of the search engine marketing mix. Many search users do not click on these because they don’t trust advertisers, although these are mainly people involved in marketing.
Chaffey, D. and Ellis-Chadwick, F., 2012. Digital marketing: strategy, implementation and practice (Vol. 5). Harlow: Pearson.