In South Africa, as well as in some other countries, it is possible to pay patent renewal fees for the lifetime of the patent in advance. With the exception of the risk of missing the first renewal fee, if renewal fees are paid for the lifetime of a patent then the risk of lapsing of the patent will not arise once this payment has been made. The costs of a renewing a South African patent for life is also cheaper than paying 17 individual renewal fees and the costs are fixed at a low base and insulated against future patent office fee increases. US patents maintenance fees cannot be paid more than 6 months before the due date.
Another way to reduce the risk of missing a patent renewal is to place your patent attorney in funds with a deposit and request that patent renewal fees should be paid automatically as they arise. This will reduce but not eliminate the risk of lapsing of a patent but patent attorneys have sophisticated diary reminder systems for renewal payments and thus reduces the risk substantially as long as they are given the funds in good time to pay the renewal fees. Ideally, the patentee should also keep a diary of all due renewal dates.
Finally, many patents lapse due to patentees relocating, changing the person responsible for renewals within their organisation, or merging with or acquiring another company and not notifying the patent attorney of these changes so that the renewal notices which are routinely sent out by patent attorneys do not reach the patentee or the person within the organisation responsible for maintaining their patent portfolio and attending to the payment of the renewal fees.